Question 1

How does the random number generator work?

Accepted Answer

The tool uses the Web Crypto API (crypto.getRandomValues) to produce cryptographically strong random numbers. For integers it applies rejection sampling to eliminate modulo bias, ensuring perfectly uniform distribution across your chosen range.

Question 2

What is the difference between Integer and Float mode?

Accepted Answer

Integer mode generates whole numbers in the closed interval [min, max] using bias-free rejection sampling. Float mode produces floating-point numbers in the half-open interval [min, max) using 32 bits of entropy per value.

Question 3

What does the Bytes mode produce?

Accepted Answer

Bytes mode fills a Uint8Array with cryptographically random bytes and encodes the result as hexadecimal, Base64, or space-separated decimal byte values. Useful for generating API keys, tokens, or initialization vectors.

Question 4

What is Big Decimal mode for?

Accepted Answer

Big Decimal mode generates arbitrary-precision decimal strings with up to 200 significant digits, far beyond the ~15-digit precision of JavaScript floats. Each digit is derived from crypto.getRandomValues, suitable for high-precision simulations or testing arbitrary-precision math libraries.

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Random Number Generator

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