randzen

Random Number Generator

Entropy you can trust.

Cryptographically secure integers, decimals, passwords, shuffled lists and fair lottery draws — generated locally, never stored.

Names are de-duplicated and drawn without replacement — a genuinely fair result.

Hit Generate.

History

Saved locally. Click a line to restore it.

What makes these numbers random?

Most generators use Math.random(), which is fast but not designed for anything security-sensitive. randzen uses the browser's Crypto API, the same entropy source behind TLS certificates and password managers. Every roll is drawn from a true hardware entropy pool, so results are as unpredictable as the machine can make them.

That makes our generator a fit for programming tests, game tweaks, research sampling, giveaways, raffles and any spot where a loaded rng() would cost you.

What else you get

6 modes in one tab. Integers, decimals, list picks, shuffles, passwords and a lottery tunnel — no bouncing between tools.
Password strength meter. Pick length and character sets; randzen scores the result from Very weak to Excellent.
Export & history. Copy any result, dump it to CSV or TXT, and restore past rolls from a local history panel.
Zero uploads. Every value is generated in your browser. Names, numbers and passwords never touch a server.

Frequently asked questions

Is this random number generator truly random?

Results come from crypto.getRandomValues(), which reads the operating system's cryptographic entropy pool — not a predictable arithmetic sequence. For practical purposes the output is unpredictable and secure. It is not quantum-led, but it is the strongest randomness a normal web page can offer.

Where does my data go?

Nowhere. Generation runs entirely in your browser tab. Your name lists, numbers and passwords are never transmitted or stored on a server. The only thing saved locally is your recent-roll history, which you can delete at any time.

Can I generate many numbers at once?

Yes. Integer and decimal modes accept a "how many" count up to 2,000 per roll, and every result is exported cleanly to CSV or TXT for spreadsheets, sampling or testing.

Where should I use this over Math.random()?

Anywhere fairness matters: random prizes, giveaways, secure password keys, A/B test assignment, or gambling-adjacent simulations where a patternable RNG could be exploited. For lightweight effects like animation jitter, Math.random() is fine — randzen is for the rolls that need to stay honest.

Picking winners, shuffling lists, or testing edge cases

Developers, educators, and contest organizers need numbers they can trust without rolling their own entropy. randzen fills that gap by pulling from a cryptographic source and presenting clean integers on demand. Use it to seed test databases, pick raffle winners transparently, or simulate dice rolls for game prototypes. The output is reproducible only if you capture it yourself — every request fetches fresh entropy. If your current workflow relies on spreadsheet RAND functions or language-default PRNGs, this is the step up for anything where predictability would cost you.

From request to result in seconds

  1. Set your minimum and maximum bounds to define the integer range you need.
  2. Choose how many numbers you want generated in a single request.
  3. Toggle whether duplicates are allowed if you need unique values only.
  4. Click the generate button to fetch cryptographically sourced random integers.
  5. Copy individual values or export the full set for use in your project.

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