# DevToys Web Pro

> DevToys Web Pro (https://devtoys.pro) is a free online developer toolkit with 30+ tools: formatters (JSON, SQL, XML), encoders/decoders (Base64, URL, JWT), converters, generators (UUID, hash, password, QR code), testers (regex, XPath, JSONPath), text, image, and network utilities. Tools process data locally in the browser — nothing is uploaded, no account or installation needed.

Available as a website, a Progressive Web App for offline use, and a browser extension for Chrome, Firefox, and Edge. Because processing is client-side, it is safe for JWT tokens, API keys, and other sensitive developer data.

## Converters

- [Converters](https://devtoys.pro/converters): Free online data conversion tools: JSON to YAML, XML to JSON, number base converter, date/timestamp converter, cron parser and more.
- [Cron Expression Parser](https://devtoys.pro/converters/cron-parser): Parse any cron expression to see the next scheduled run dates. Instantly convert crontab syntax to human-readable text — free and private.
- [Cron Expression Generator](https://devtoys.pro/converters/cron-generator): Build cron expressions visually with an interactive cron builder. Preview the next scheduled dates and copy the final crontab syntax instantly.
- [Date Converter](https://devtoys.pro/converters/date-converter): Convert Unix timestamps to human-readable dates and vice versa. Supports milliseconds, ISO 8601, and local timezone — instant, no signup needed.
- [JSON Array to Table](https://devtoys.pro/converters/json-csv): Convert a JSON array to a table, CSV, or TSV format instantly. Paste your array and download structured data ready for Excel or databases.
- [JSON <> YAML Converter](https://devtoys.pro/converters/json-yaml): Convert JSON to YAML and YAML to JSON in one click. Instant bidirectional conversion with syntax validation — free, private, no server upload.
- [Number Base Converter](https://devtoys.pro/converters/number-base): Convert numbers between binary, decimal, hexadecimal, and octal bases. Instant radix conversion with multiple outputs — free online tool.
- [Roman Numeral Converter](https://devtoys.pro/converters/roman-numeral): Convert between Roman numerals and Arabic numbers instantly. Supports values from I to MMMCMXCIX — free online Roman numeral converter.
- [XML <> JSON Converter](https://devtoys.pro/converters/xml-json): Convert XML to JSON and JSON to XML instantly. Bidirectional conversion with structure preservation — free online XML/JSON converter.
- [Markdown <> HTML Converter](https://devtoys.pro/converters/markdown-html): Convert Markdown to HTML and HTML back to Markdown instantly. Get clean, standards-compliant output — free online Markdown/HTML converter.
- [HTML to JSX Converter](https://devtoys.pro/converters/html-jsx): Convert HTML markup to JSX syntax for React instantly. Handles class→className, inline styles, and self-closing tags — free online tool.
- [JSON <> TOML Converter](https://devtoys.pro/converters/json-toml): Convert JSON to TOML and TOML to JSON instantly. Perfect for Cargo.toml and pyproject.toml workflows — free online JSON/TOML converter.
- [YAML <> TOML Converter](https://devtoys.pro/converters/yaml-toml): Convert YAML to TOML and TOML to YAML instantly. Ideal for Cargo.toml and config migration workflows — free online YAML/TOML converter.
- [OPML RSS URL Extractor](https://devtoys.pro/converters/opml-rss): Extract all RSS feed URLs from an OPML subscription file instantly. Perfect for migrating feed readers — free online OPML extractor.
- [RSS URLs to OPML Generator](https://devtoys.pro/converters/rss-opml): Generate an OPML subscription file from a list of RSS feed URLs instantly. Export your feed collection to any reader — free online tool.
- [Data Size / Byte Converter](https://devtoys.pro/converters/data-size): Convert between bits, bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes. Supports binary (KiB) and decimal (KB) standards.
- [cURL to Code Converter](https://devtoys.pro/converters/curl-code): Convert cURL commands to JavaScript, Python, Go, PHP, Ruby, and more. Instantly generate API code from any curl request — free online tool.
- [JSON to Code Generator](https://devtoys.pro/converters/json-to-code): Generate TypeScript, Go, Python, Java, C#, and Swift types from JSON. Instantly create typed models from any API response — free online tool.
- [chmod Calculator](https://devtoys.pro/converters/chmod): Calculate Unix file permissions with visual checkboxes. Convert between octal (755, 644), symbolic (rwxr-xr-x), and chmod commands instantly.
- [Unit Converter](https://devtoys.pro/converters/unit): Convert between units of length, weight, temperature, data size, time, and more. Instant bidirectional conversion — free online unit converter.
- [Docker Run to Compose](https://devtoys.pro/converters/docker-compose): Convert docker run commands to docker-compose.yml files. Paste a docker run command and get a ready-to-use compose file — free online tool.
- [Protobuf Decoder / Encoder](https://devtoys.pro/converters/protobuf): Decode and encode Protocol Buffer messages. Paste binary or Base64 protobuf data and see the decoded fields — free online protobuf tool.
- [JSON Table Viewer](https://devtoys.pro/converters/json-table): Visualise any JSON array as a sortable, filterable table. Auto-detects columns, flattens nested objects with dot notation, and exports to CSV — free and private.
- [Coordinates Converter](https://devtoys.pro/converters/coordinates): Convert GPS coordinates between Decimal Degrees (DD), Degrees Minutes Seconds (DMS), and UTM. Auto-detect any format — free, private, no server upload.
- [CBOR / MessagePack Codec](https://devtoys.pro/converters/cbor-msgpack): Encode JSON to CBOR or MessagePack binary and decode it back. Compare payload sizes and inspect hex or Base64 output — free, private, runs in your browser.
- [VarInt Encoder / Decoder](https://devtoys.pro/converters/varint): Encode unsigned integers as Protobuf-style LEB128 VarInts and decode them back. Inspect hex or Base64 output — free, private, runs in your browser.
- [Text ↔ Binary Converter](https://devtoys.pro/converters/text-binary): Convert text to binary (8-bit per char, UTF-8) and back. Configurable bit grouping and separator — free online text-to-binary converter.
- [Text ↔ Unicode Converter](https://devtoys.pro/converters/text-unicode): Convert text to Unicode code points (U+XXXX, \uXXXX, &#N;) and decode escape sequences back to text — free online Unicode converter.
- [Swap Endianness](https://devtoys.pro/converters/endianness): Swap byte order between little-endian and big-endian for hex data. Configurable word size (2/4/8 bytes) — free online endianness converter.
- [NATO Phonetic Alphabet Converter](https://devtoys.pro/converters/nato): Convert any text to the NATO phonetic alphabet (Alpha, Bravo, Charlie...). Supports digits and aviation pronunciation — free online tool.

## Network

- [Network](https://devtoys.pro/network): Network tools for subnetting, IP conversion, range expansion, and IPv6 parsing.
- [IPv4 Subnet Calculator](https://devtoys.pro/network/ipv4-subnet-calculator): Calculate subnet masks, usable host ranges, and broadcast addresses from any CIDR notation. Free online IPv4 subnet calculator for network planning.
- [IPv4 Address Converter](https://devtoys.pro/network/ipv4-address-converter): Convert IPv4 addresses between dotted decimal, hexadecimal, and binary formats instantly. Free online IP address converter for network debugging.
- [IPv4 Range Expander](https://devtoys.pro/network/ipv4-range-expander): Expand an IPv4 address range into a full list of addresses and count usable hosts. Free online IP range expander for firewall and ACL rules.
- [IPv6 Parser / Expander](https://devtoys.pro/network/ipv6-parser): Parse, expand, and compress IPv6 addresses instantly. Convert between full and abbreviated forms — free online IPv6 address parser and validator.
- [TLS Version Checker](https://devtoys.pro/network/tls-checker): Check TLS/SSL version, certificate details, and cipher suite for any hostname. Verify HTTPS security configuration — free online TLS checker.
- [IPv6 ULA Generator](https://devtoys.pro/network/ipv6-ula): Generate RFC 4193 IPv6 Unique Local Addresses (fd00::/8) for private networks. Derived from MAC + NTP time via SHA-1 — free, private, runs in your browser.
- [MAC Address Vendor Lookup (OUI)](https://devtoys.pro/network/mac-lookup): Look up the manufacturer of any MAC address using the IEEE OUI registry. 39,000+ entries, all queried locally — free, private, no API calls.

## Encoders / Decoders

- [Encoders / Decoders](https://devtoys.pro/encoders-decoders): Free online encoding and decoding tools: Base64, URL encoder, HTML entities, JWT decoder, GZip compression, certificate decoder and more.
- [Base64 Image Encoder / Decoder](https://devtoys.pro/encoders-decoders/base64-image): Encode images to Base64 data URLs and decode Base64 strings back to images. Instant conversion for CSS backgrounds and HTML embeds — free.
- [Base64 Text Encoder / Decoder](https://devtoys.pro/encoders-decoders/base64): Encode text to Base64 and decode Base64 strings instantly. All processing happens in your browser — no data sent to any server, completely free.
- [Certificate Decoder](https://devtoys.pro/encoders-decoders/certificate): Decode X.509 SSL/TLS certificates to view subject, issuer, SAN entries, validity dates, and fingerprints. Free online certificate decoder.
- [GZip Compress / Decompress](https://devtoys.pro/encoders-decoders/gzip): Compress text with GZip and decompress GZip data instantly in your browser. Reduce payload sizes for APIs and storage — free online GZip tool.
- [HTML Text Encoder / Decoder](https://devtoys.pro/encoders-decoders/html): Encode special characters to HTML entities and decode HTML entities back to text. Prevent XSS by escaping user content safely — free online tool.
- [JWT Encoder / Decoder](https://devtoys.pro/encoders-decoders/jwt): Decode and inspect JWT tokens to view header, payload, and claims instantly. All decoding happens in your browser — safe for production tokens.
- [URL Encoder / Decoder](https://devtoys.pro/encoders-decoders/url): Percent-encode URLs and decode URL-encoded strings instantly. Handles encodeURIComponent and encodeURI rules — free online URL encoder/decoder.
- [Quoted-Printable Encoder / Decoder](https://devtoys.pro/encoders-decoders/quoted-printable): Encode and decode Quoted-Printable email content (RFC 2045) instantly. Debug MIME messages and email encoding issues — free online QP tool.
- [Hex to ASCII / ASCII to Hex Converter](https://devtoys.pro/encoders-decoders/hex-ascii): Convert hexadecimal values to ASCII text and ASCII to hex instantly. Useful for debugging binary protocols and network packets — free online tool.
- [Base58 Encoder / Decoder](https://devtoys.pro/encoders-decoders/base58): Encode and decode Base58 strings used in Bitcoin addresses and IPFS content hashes instantly. Free online Base58 encoder/decoder.
- [GZip Processor](https://devtoys.pro/encoders-decoders/gzip-processor): Server-side high-performance GZip compression with configurable levels (1–9). Optimize API payloads and CDN assets — enterprise compression tool.
- [Base32 Encoder / Decoder](https://devtoys.pro/encoders-decoders/base32): Encode and decode Base32 strings used in TOTP secrets and RFC 4648 applications. Free online Base32 encoder/decoder.
- [Bzip2 Decompressor](https://devtoys.pro/encoders-decoders/bzip2): Decompress bzip2 (.bz2) files and data in your browser. Paste Base64 or hex-encoded bzip2 data, or drop a .bz2 file — instant client-side decompression.
- [Base62 Encoder / Decoder](https://devtoys.pro/encoders-decoders/base62): Encode and decode Base62 strings. URL-safe alphanumeric encoding used by URL shorteners and short ID systems — free online tool.

## Formatters

- [Formatters](https://devtoys.pro/formatters): Free online code formatters: JSON beautifier, JavaScript formatter, CSS formatter, HTML formatter, SQL formatter, XML prettifier. Format, indent, and minify your code instantly.
- [JSON Formatter](https://devtoys.pro/formatters/json): Format, beautify, and validate JSON instantly. Pretty-print or minify JSON data for APIs, configs, and debugging — free online JSON formatter.
- [SQL Formatter](https://devtoys.pro/formatters/sql): Format and beautify SQL queries with proper indentation and keyword casing. Supports MySQL, PostgreSQL, SQLite — free online SQL formatter.
- [XML Formatter](https://devtoys.pro/formatters/xml): Format, indent, and validate XML documents instantly. Beautify or minify XML for APIs and configs — free online XML formatter and validator.
- [CSS Formatter](https://devtoys.pro/formatters/css): Format and beautify CSS stylesheets with consistent indentation and spacing. Clean up messy CSS code instantly — free online CSS formatter.
- [JavaScript Formatter](https://devtoys.pro/formatters/javascript): Format and beautify JavaScript code with proper indentation. Instantly clean up minified or messy JS — free online JavaScript formatter.
- [HTML Formatter](https://devtoys.pro/formatters/html): Format and beautify HTML markup with proper indentation and structure. Clean up messy templates instantly — free online HTML code formatter.
- [TOML Formatter](https://devtoys.pro/formatters/toml): Format and validate TOML configuration files with proper indentation. Perfect for Cargo.toml and pyproject.toml — free online TOML formatter.
- [YAML Formatter](https://devtoys.pro/formatters/yaml): Format and validate YAML configuration files with correct indentation. Spot structural errors instantly — free online YAML formatter and validator.
- [Python Formatter](https://devtoys.pro/formatters/python): Format and beautify Python code with proper indentation. Uses Ruff-compatible formatting rules — free online Python formatter.
- [SCSS Formatter](https://devtoys.pro/formatters/scss): Format and beautify SCSS/Sass code with proper indentation and nesting. Uses Prettier formatting — free online SCSS formatter.
- [LESS Formatter](https://devtoys.pro/formatters/less): Format and beautify LESS stylesheets with proper indentation and nesting. Uses Prettier formatting — free online LESS formatter.
- [GraphQL Formatter](https://devtoys.pro/formatters/graphql): Format and beautify GraphQL queries, mutations, and schemas. Uses Prettier with lazy-loaded GraphQL plugin — free, private, in-browser.

## Generators

- [Generators](https://devtoys.pro/generators): Free online generators: UUID/GUID generator, password generator, hash/checksum calculator, Lorem Ipsum text, and QR codes.
- [Hash / Checksum Generator](https://devtoys.pro/generators/hash-checksum): Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text or files instantly. Verify file integrity and checksums — free online hash generator.
- [HMAC Generator](https://devtoys.pro/generators/hmac): Generate HMAC-SHA256, HMAC-SHA512, and HMAC-SHA1 signatures for messages. Verify webhook signatures and API authentication — free online HMAC tool.
- [Bcrypt Generator / Validator](https://devtoys.pro/generators/bcrypt): Generate and verify bcrypt password hashes with configurable cost factor (rounds). Test bcrypt hash security in your browser — free online bcrypt tool.
- [Lorem Ipsum Generator](https://devtoys.pro/generators/lorem-ipsum): Generate Lorem Ipsum placeholder text by paragraphs, sentences, or words. Fill designs and prototypes with dummy text instantly — free online tool.
- [Fake Data / Faker Generator](https://devtoys.pro/generators/fake-data): Generate realistic fake test data with User, Employee, Product, and Order templates. Export as JSON, YAML, CSV, or SQL — free online faker tool.
- [Password Generator](https://devtoys.pro/generators/password): Generate strong, random passwords with custom length, symbols, and character sets. Create secure passwords instantly — free online password generator.
- [UUID Generator & Decoder](https://devtoys.pro/generators/uuid): Generate UUID v1, v4 (GUID), v6, and v7 and decode existing UUIDs. Create unique identifiers for databases and APIs — free online UUID generator.
- [QR Code Encoder / Decoder](https://devtoys.pro/generators/qr-code): Generate QR codes from text, URLs, or any string and scan QR codes from images. Export as SVG or PNG — free online QR code generator and reader.
- [Basic Auth Generator](https://devtoys.pro/generators/basic-auth): Generate Base64-encoded HTTP Basic Authentication credentials and Authorization headers. Build and test API auth instantly — free online tool.
- [Hash Calculator](https://devtoys.pro/generators/hash-calculator): Calculate MD5, SHA-256, SHA-512, and BLAKE2 hashes using native server-side crypto. High-performance bulk hashing for enterprise use cases.
- [OTP Generator (TOTP/HOTP)](https://devtoys.pro/generators/otp): Generate TOTP and HOTP one-time passwords for 2FA testing. Compatible with Google Authenticator and Authy — free online OTP generator and tester.
- [RSA Key Pair Generator](https://devtoys.pro/generators/rsa-keys): Generate RSA 2048/4096-bit public and private key pairs in PEM format. Create asymmetric keys for encryption and signing — free online RSA tool.
- [Meta Tag Generator (OG/Twitter)](https://devtoys.pro/generators/meta-tags): Generate Open Graph and Twitter Card meta tags for your web pages. Preview how your site appears on social media — free online meta tag generator.
- [MAC Address Generator](https://devtoys.pro/generators/mac-address): Generate random MAC addresses for testing and development. Supports multiple formats and vendor prefixes — free online MAC address generator.
- [Scrypt Hash Generator](https://devtoys.pro/generators/scrypt): Generate scrypt password hashes with configurable cost parameters. Memory-hard key derivation for secure password storage — free online scrypt tool.
- [BIP39 Mnemonic Generator](https://devtoys.pro/generators/bip39): Generate BIP39 mnemonic seed phrases for cryptocurrency wallets. Create 12 or 24-word recovery phrases — free online BIP39 generator.
- [SVG Placeholder Generator](https://devtoys.pro/generators/svg-placeholder): Generate SVG placeholder images with custom dimensions, colours, and text. Get inline data URIs ready to paste into HTML or CSS — free online tool.
- [Random Number Generator](https://devtoys.pro/generators/random-number): Generate cryptographically random integers, floats, byte sequences, and arbitrary-precision decimals. Bias-free rejection sampling via the Web Crypto API — free online random number generator.
- [Random Port Generator](https://devtoys.pro/generators/random-port): Generate cryptographically random TCP/UDP port numbers. Skip well-known and commonly-used ports — free online random port picker.
- [CSS Triangle Generator](https://devtoys.pro/generators/css-triangle): Generate CSS for triangles in 8 directions using the border trick. Adjust size and color, preview live, copy the CSS — free online CSS triangle maker.

## Text

- [Text](https://devtoys.pro/text): Free online text tools: text diff/compare, HTML preview, markdown preview, text analyzer, list comparer, and string escape/unescape utilities.
- [Text Escape / Unescape](https://devtoys.pro/text/text-escape): Escape and unescape strings for JSON, JavaScript, and XML. Remove or add backslash escaping to prevent parsing errors — free online string tool.
- [List Comparer](https://devtoys.pro/text/list-compare): Compare two lists to find common items, unique differences, and duplicates. Instantly diff sorted or unsorted lists — free online list comparator.
- [Line Utilities](https://devtoys.pro/text/line-utilities): Sort lines alphabetically, remove duplicate lines, strip whitespace, and filter text. Batch text line operations instantly — free online tool.
- [HTML Preview](https://devtoys.pro/text/html-preview): Preview HTML code in a live sandboxed browser window instantly. Test HTML templates and snippets without a local server — free online HTML viewer.
- [Markdown Preview](https://devtoys.pro/text/markdown): Preview Markdown documents with GitHub-style rendering. See exactly how your README or blog post will look — free online Markdown editor and viewer.
- [Text Analyzer and Utilities](https://devtoys.pro/text/text-analyzer): Analyze text for word count, character count, and reading time. Convert case to camelCase, snake_case, UPPER, lower — free online text analyzer.
- [Text Comparer](https://devtoys.pro/text/text-comparer): Compare two texts side by side and highlight every difference. Find changes between code versions or documents — free online text diff tool.
- [String Replacer](https://devtoys.pro/text/string-replacer): Find and replace text with plain string or regex patterns. Batch-replace across multi-line content instantly — free online string replacer tool.
- [Mermaid Diagram Editor](https://devtoys.pro/text/mermaid-editor): Write Mermaid diagram syntax and see a live preview. Create flowcharts, sequence diagrams, class diagrams, and more — free online Mermaid editor.
- [Defang / Fang URLs & IPs](https://devtoys.pro/text/defang-url): Defang URLs and IP addresses for safe sharing in reports and tickets. Refang them back for use — free online defang/fang tool.
- [Extract URLs / Emails / IPs](https://devtoys.pro/text/extractors): Extract all URLs, email addresses, and IP addresses from any text. Parse logs and documents for indicators — free online text extractor.
- [URL Slug Generator](https://devtoys.pro/text/slugify): Convert any text to a URL-friendly slug. Handles Unicode, special characters, and multiple languages — free online slugify tool.
- [Prefix / Suffix Lines](https://devtoys.pro/text/prefix-suffix): Add a prefix or suffix to every line of text. Bulk prepend or append strings to multiple lines — free online tool.
- [ASCII Art Text Generator](https://devtoys.pro/text/ascii-art): Convert text to ASCII art using FIGlet fonts. Generate large text banners for terminals, comments, and README files — free online ASCII art generator.
- [Emoji Picker & Search](https://devtoys.pro/text/emoji-picker): Browse and search the full Unicode emoji set by keyword or category. Click any emoji to copy it to your clipboard — free, instant, no signup needed.
- [String Obfuscator / PII Masker](https://devtoys.pro/text/string-obfuscator): Mask emails, credit cards, phone numbers, IPs, and JWTs in any text. Redact PII from logs and documents — free online string obfuscator.
- [Strip HTML Tags](https://devtoys.pro/text/strip-html): Remove all HTML markup from text instantly. Extract plain text, decode entities, and strip scripts and styles — free, private, runs in your browser.
- [CSS Playground](https://devtoys.pro/text/css-playground): Live HTML + CSS sandbox with instant preview. Experiment with selectors, gradients, and layouts in a sandboxed iframe — free, private, runs in your browser.
- [SVG Preview / Editor](https://devtoys.pro/text/svg-preview): Edit SVG markup and see it rendered live. Inspect width, height, viewBox, element count, and copy as URL-encoded data: URI — free, private, in-browser.
- [Outlook Safelink Decoder](https://devtoys.pro/text/safelink-decoder): Decode Outlook ATP, Proofpoint URLDefense (v1/v2/v3), Mimecast, Barracuda, and generic redirector URLs back to their originals. Single or bulk paste — free, private, in-browser.

## Documents

- [Documents](https://devtoys.pro/documents): Free online document tools: Word document comparison, PowerPoint extractor, and document processing utilities.
- [Word Document Comparison](https://devtoys.pro/documents/word-comparison): Compare two Word (.docx) documents and highlight every text difference. Review changes between document versions instantly — free online Word diff tool.
- [PowerPoint Content Extractor](https://devtoys.pro/documents/powerpoint-extractor): Extract all text, images, and metadata from PowerPoint files (.pptx, .ppsx). Get slide content without PowerPoint — free online PPTX extractor.

## Testers

- [Testers](https://devtoys.pro/testers): Free online testing tools: regex tester, XSD pattern tester, JSONPath evaluator, URL parser, and XML validator. Test and debug patterns and queries instantly.
- [JSONPath Tester](https://devtoys.pro/testers/jsonpath): Test JSONPath expressions against JSON data and see matching results instantly. Debug API queries and JSON selectors — free online JSONPath tester.
- [JSON Schema Validator](https://devtoys.pro/testers/json-schema-validator): Validate JSON data against JSON Schema drafts 04, 06, 07, and 2019-09. Catch schema errors before they reach production — free online validator.
- [IBAN Validator](https://devtoys.pro/testers/iban): Validate International Bank Account Numbers (IBAN) with checksum verification. Check IBAN format and country codes instantly — free online tool.
- [Regular Expression Tester](https://devtoys.pro/testers/regex): Test JavaScript regular expressions with real-time match highlighting. Debug patterns, groups, and flags instantly — free online regex tester.
- [XSD Regex Pattern Tester](https://devtoys.pro/testers/xsd-regex): Test XSD regex patterns (XML Schema Definition) against sample strings. Validate pattern constraints for XML schemas — free online XSD pattern tester.
- [URL Parser](https://devtoys.pro/testers/url-parser): Parse any URL into its components: protocol, host, path, query parameters, and fragment. Debug and inspect URLs — free online URL parser.
- [XML Validator](https://devtoys.pro/testers/xml-validator): Validate XML data for correct syntax and well-formed structure. Catch missing tags, bad attributes, and parse errors — free online XML validator.
- [User Agent Parser](https://devtoys.pro/testers/user-agent-parser): Parse User-Agent strings to extract browser name, version, OS, and device type. Debug browser detection logic — free online UA parser.
- [Query String Parser](https://devtoys.pro/testers/query-string-parser): Parse and decode URL query string parameters into key-value pairs. Debug query strings from API logs — free online query string parser.
- [XML / XSD Validator](https://devtoys.pro/testers/xml-xsd-validator): Validate XML documents against XSD schemas for structure and type compliance. Enterprise XML schema validation — free online XML/XSD validator.
- [Password Strength Checker](https://devtoys.pro/testers/password-strength): Check password strength, entropy, and estimated crack time using the zxcvbn algorithm. Get actionable security tips — free online password checker.
- [JSONata Expression Tester](https://devtoys.pro/testers/jsonata): Test JSONata expressions against JSON data with live results. Debug JSON queries and transformations — free online JSONata tester.
- [Phone Number Parser](https://devtoys.pro/testers/phone-parser): Parse and validate international phone numbers. Extract country code, national number, and format type — free online phone number parser.
- [Keyboard Keycode Viewer](https://devtoys.pro/testers/keycode): Press any key to see its JavaScript keycode, key, code, and which values. Debug keyboard event handlers — free online keycode viewer.
- [JSON Diff Viewer](https://devtoys.pro/testers/json-diff): Compare two JSON documents side by side and see exactly what changed. Highlights added, removed, and modified keys with a structured visual diff — free and private.
- [XPath Tester](https://devtoys.pro/testers/xpath): Test XPath expressions against XML or HTML documents with real-time results. Debug node selections, attributes, and text content — free online XPath tester.
- [CSS Selector Tester](https://devtoys.pro/testers/css-selector): Test CSS selectors against HTML and see matching elements in real time. Debug querySelectorAll queries and selector specificity — free online CSS selector tester.
- [Email Normalizer](https://devtoys.pro/testers/email-normalizer): Normalize and deduplicate email addresses: strip Gmail dots, remove plus aliases, and lowercase. Identify duplicate addresses across bulk lists — free online email normalizer.
- [WebSocket Tester](https://devtoys.pro/testers/websocket): Connect to any ws:// or wss:// endpoint, send messages, see responses with JSON pretty-printing, and persist history locally. Free, private, in-browser WebSocket client.

## Colors

- [Colors](https://devtoys.pro/colors): Free online color tools: color picker, color converter, palette generator, contrast calculator, and color blindness simulator.
- [Color Picker & Converter](https://devtoys.pro/colors/color-picker): Pick colors and instantly convert between HEX, RGB, HSL, and HSV formats. Generate color codes for CSS and design — free online color picker.
- [Color Contrast Calculator](https://devtoys.pro/colors/color-contrast): Calculate color contrast ratios and check WCAG AA/AAA accessibility compliance. Ensure readable text for all users — free online contrast checker.
- [Color Blindness Simulator](https://devtoys.pro/colors/color-blindness): Simulate how images appear to users with protanopia, deuteranopia, and tritanopia. Test color accessibility for inclusive design — free online tool.
- [Color Palette Generator](https://devtoys.pro/colors/palette-generator): Generate harmonious color palettes with complementary, analogous, triadic, and tetradic color schemes. Create beautiful palettes for your designs — free online tool.
- [Tints & Shades Generator](https://devtoys.pro/colors/tints-shades): Generate lighter tints and darker shades from any base color. Create smooth color gradations for UI design and branding — free online tool.
- [Color Palette Extractor](https://devtoys.pro/colors/palette-extractor): Extract dominant colors from any image. Upload a photo and get the main color palette with HEX, RGB, and HSL values — free online tool.
- [Color Harmonies Generator](https://devtoys.pro/colors/harmonies): Generate complementary, analogous, triadic, tetradic, split-complementary, and monochromatic color harmonies from any base color — free online tool.

## Images

- [Images](https://devtoys.pro/images): Free online image tools: image converter, compressor, resizer, cropper, and image boxing/letterboxing utilities.
- [Image Converter](https://devtoys.pro/images/image-converter): Convert images between PNG, JPEG, WebP, and other formats losslessly in your browser. No upload to any server — free online image converter.
- [Image Compressor](https://devtoys.pro/images/image-compressor): Compress PNG and JPEG images to reduce file size for faster web pages. Optimize images without losing quality — free online image compressor.
- [Image Resizer](https://devtoys.pro/images/image-resizer): Resize images by exact pixel dimensions or percentage scale. Reduce file size for web and email — free online image resizer, no signup needed.
- [Image Cropper](https://devtoys.pro/images/image-cropper): Crop images by selecting a rectangular area with drag-and-drop precision. Remove unwanted borders and backgrounds — free online image cropper.
- [Image Boxing](https://devtoys.pro/images/image-boxing): Fit images to a canvas with letterbox or pillarbox padding. Add borders to make any image fill a target aspect ratio — free online image boxing tool.
- [Image Processor](https://devtoys.pro/images/image-processor): Server-side high-performance image processing with AVIF and HEIF compression support. Optimize next-gen image formats at scale — enterprise tool.
- [Image Compare Slider](https://devtoys.pro/images/image-compare): Compare two images side-by-side with a draggable slider. Reveal before/after differences for image compression, edits, or AI upscaling — free, private.
- [SVG Optimizer (SVGO)](https://devtoys.pro/images/svg-optimizer): Optimize SVG files in your browser using SVGO with full plugin toggles. Lazy-loaded ~80KB chunk; remove metadata, collapse paths, shrink colors — free, private.

## References

- [References](https://devtoys.pro/references): Free online developer reference tools: HTTP status codes, MIME types, and other quick-reference guides for developers.
- [HTTP Status Codes Reference](https://devtoys.pro/references/http-status): Look up any HTTP status code with descriptions, categories, and usage guidance. Complete reference for 1xx, 2xx, 3xx, 4xx, and 5xx codes — free online tool.
- [MIME Types Lookup](https://devtoys.pro/references/mime-types): Look up MIME types by type name or file extension. Search all 2500+ registered MIME types with extensions, compressibility, and source — free online reference.
- [Git Command Finder](https://devtoys.pro/references/git-commands): Find the exact git command for your scenario — undo a commit, delete a branch, recover lost work, stash, rebase, cherry-pick. 40+ recipes with explanations and safety warnings.
- [CSS Cursors Reference](https://devtoys.pro/references/css-cursors): Browse all 36 native CSS cursor values with live hover previews and copy-ready snippets. Quick reference for pointer, grab, resize, zoom, and more.
- [Regex Cheatsheet](https://devtoys.pro/references/regex-cheatsheet): 8-category regex reference: character classes, anchors, groups, lookaround, quantifiers, flags, and more. Click any token to copy it. Browse the same data the regex tester drawer uses.

## Calculators

- [Calculators](https://devtoys.pro/calculators): Free online calculators: math expression evaluator, scientific calculator, and developer math utilities.
- [Math Expression Evaluator](https://devtoys.pro/calculators/math): Evaluate mathematical expressions with variables, functions, and unit conversions. Supports algebra, trigonometry, and more — free online math evaluator.
- [Percentage Calculator](https://devtoys.pro/calculators/percentage): Calculate percentages, percentage change, and percentage of a number. Solve common percentage problems instantly — free online calculator.
- [Entropy Calculator](https://devtoys.pro/calculators/entropy): Calculate Shannon entropy and character frequency distribution of any text or data. Measure randomness and information density — free online tool.
- [Checksum Calculator](https://devtoys.pro/calculators/checksum): Calculate CRC-8, CRC-16, CRC-24, CRC-32, Adler-32 checksums and Luhn validation for any text or hex input. Free online checksum calculator.

## Astrology

- [Astrology](https://devtoys.pro/astrology): Free online astrology calculators: zodiac sign finder, Chinese zodiac, biorhythm, numerology, compatibility, moon phase, planetary hours, and natal chart tools.
- [Zodiac Sign Calculator](https://devtoys.pro/astrology/zodiac-sign): Calculate your Western zodiac sign based on your date of birth. Find your sun sign, element, and ruling planet — free online zodiac calculator.
- [Chinese Zodiac Calculator](https://devtoys.pro/astrology/chinese-zodiac): Find your Chinese zodiac animal sign and element based on your birth year. Discover your lunar year animal — free online Chinese zodiac calculator.
- [Biorhythm Calculator](https://devtoys.pro/astrology/biorhythm): Calculate your biorhythm cycles for physical, emotional, and intellectual rhythms. Visualize your daily biorhythm chart — free online biorhythm calculator.
- [Numerology Calculator](https://devtoys.pro/astrology/numerology): Calculate your numerology numbers including life path, expression, and soul urge numbers from your name and birth date — free online numerology calculator.
- [Zodiac Compatibility Calculator](https://devtoys.pro/astrology/compatibility): Check zodiac compatibility between two signs. Find out how well your signs match in love, friendship, and communication — free online compatibility calculator.
- [Moon Phase Calculator](https://devtoys.pro/astrology/moon-phase): View the current moon phase and calculate moon phases for any date. See illumination percentage and lunar cycle details — free online moon phase calculator.
- [Planetary Hours Calculator](https://devtoys.pro/astrology/planetary-hours): Calculate the current planetary hour and daily planetary hour table for your location. Find the ruling planet for any hour — free online planetary hours calculator.
- [Natal Chart Generator](https://devtoys.pro/astrology/natal-chart): Generate your birth chart (natal chart) based on your date, time, and place of birth. View planet positions and house placements — free online natal chart generator.

## Learn

- [Blog](https://devtoys.pro/blog): Guides on encoding, hashing, image formats, and developer workflows

## Optional

- [Sitemap](https://devtoys.pro/sitemap.xml): All indexable pages, including localized versions