Web Crypto API · rejection sampling · no tracking

Random, done right.

A strong password generator, a configurable number generator, and a 10-slot picker. Every result is generated using cryptographic randomness — the browser's Web Crypto API — with the modulo bias removed, so each outcome is equally likely. Generate manually, or let auto mode roll once every 10 seconds.

crypto.getRandomValues() Bias: removed Generated this visit: 0

Random Number Generator

Numbers in a range, or with an exact digit count.

Set it up and generate.

10-Slot Picker

Name 10 slots, pick a winner (0–9). Names are saved.

Edit the slots, then spin.

How each result is generated

Many “random” sites use Math.random() — fine for a toy, but not cryptographic, and biased the moment you map it onto a range. WD Random is generated using cryptographic randomness instead, and shows the details of your last generation below. This panel reports the method used; it isn't a proof of randomness.

SOURCE

crypto.getRandomValues() — the browser's Web Crypto API, backed by your operating system's CSPRNG. Not Math.random().

METHOD

Bounded integers use rejection sampling, so the % operator never skews the odds — every value in a range is equally likely.

BIAS

Modulo bias is removed by discarding the small unusable tail of each 32-bit draw before mapping onto your range.

RUNS LOCALLY

100% in your browser. Nothing is sent to a server, logged, or stored — apart from your slot names, which stay in this browser's localStorage.

▌ LAST GENERATION — UPDATES ON EVERY ROLL
Source
Web Crypto API · crypto.getRandomValues()
Method
rejection sampling
Selected settings
Bias status
removed — uniform distribution
Generated
Generations this visit
0

More quick tools

manual

Lucky Number

One number, 1–9,999,999.

Tap to reveal.

Coin Flip

Heads or tails, with stats.

No flips yet.

Dice Roller

d4–d100, one or many.

Pick a die and roll.

Lottery Picker

K unique from N, optional Powerball.

Draw your ticket.

Percentage Roll

Roll against a success chance.

Enter a chance, then roll.

Weighted Random

Outcomes with custom odds.

0%
0%
0%
Weights are normalised for you.

Random Color

Hex color with live preview.

Click the hex to copy.