Random Number, Letter & Dice Generator
Random integers in any range (with or without repeats), random letters, dice rolls and coin flips from one seeded generator, so any draw can be replayed.
A list of numbers, letters, dice totals or coin results with sum, mean and counts, the size of the space it was drawn from, and a seed that regenerates the same draw.
Example: Five integers between 1 and 100 with repeats; ten unique numbers from 1–10 are a shuffle of the whole range (sum 55); 3 × 2d6 gives three totals between 2 and 12 from a space of 36.
Fair draws,
and the seed that made them.
How each mode draws, what “unique” changes, and why this is not a password generator.
The generator
Every mode uses one pseudo-random generator, mulberry32, a small 32-bit algorithm whose output is fully determined by its seed. A fresh seed comes from the browser's cryptographic random source each time you press Regenerate; the seed is shown with the result and can be typed back in to reproduce exactly the same numbers — useful when a draw has to be checked or repeated. An integer in [min, max] is min + ⌊u·(max − min + 1)⌋ with u uniform in [0, 1), so every value in the range is equally likely.
Modes
Numbers and letters can be drawn with repeats (each pick independent) or without: the whole range is shuffled with a Fisher–Yates shuffle and the first n taken, so a unique draw of the full range is a random permutation. Dice rolls each die independently and adds them — 2d6 has 36 equally likely outcomes but a total of 7 is six times likelier than 2, which the per-die breakdown makes visible. Coins are a single uniform value compared with 0.5. The space size shown is the number of equally likely outcomes of one draw.
What it is not for
mulberry32 is fine for games, sampling and test data, but it is a small predictable generator: never use it for passwords, tokens, keys or anything an adversary might want to guess. Nothing leaves the browser; the same four anonymous usage counts as the rest of the site apply.
SOURCES
- mulberry32 PRNG (Tommy Ettinger, public domain) seeded from the Web Crypto API; Fisher–Yates shuffle for draws without replacement
Last reviewed 19 September 2026. How results are checked: How we verify.