Is Math.random() suitable for security tokens?

No. Math.random() uses a pseudo-random generator seeded from the page start. Output is predictable enough that someone watching a few values can guess the next one. For anything security-adjacent (session IDs, password resets, CSRF tokens, encryption keys), use Generate Random Bytes, which calls crypto.getRandomValues() and uses the OS cryptographic random source.

How random is the output actually?

Generate Random Bytes uses the Web Crypto API, which most browsers back with the OS CSPRNG (/dev/urandom on Linux, CryptGenRandom on Windows, SecRandomCopyBytes on macOS). For scientific work needing audited randomness, use a dedicated library or hardware source. For every practical web-dev use case, these are indistinguishable from true random.

Can I generate thousands of values at once?

Yes. Each generator accepts a count parameter with no hard cap from the tool itself. The only limit is browser memory. A million 32-bit random binary strings finishes in a second or two on a modern laptop.

Why are results different every time?

That is the point. Each run reseeds (for cryptographically secure bytes) or pulls fresh pseudo-random state (for letters and binary). If you need reproducible random output for tests, seed your own generator in code. These tools are for fresh randomness on demand.

Are the generated values sent to a server?

No. All four generators run entirely in the browser. Bytes, letters, binary, and bitmap pixels never leave the page. The browser network tab confirms no requests are issued during generation.

Generators

Generators cover the jobs where a developer, tester, or teacher needs random data right now: a batch of 50 test names for a seed script, a bit-string to verify a binary parser, 32 secure bytes for a session token, or a random bitmap to test an image pipeline. 36 browser-based utilities, each producing data that is either cryptographically secure (for tokens and keys) or statistically fair (for test fixtures and teaching).

All Image139 Developer97 Date & Time95 Number84 Text84 Document51 Binary & Encoding48 Math & Science45 Unicode42 Hex37 Generators36 UTF-833 ASCII31 Fractal29 SEO28 WebP28 CSV26 JSON24 Marketing20 Financial19 Security15 Conversion15 Health & Fitness14

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