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Générateur de Nombres Aléatoires

Obtenez des nombres au hasard en un clic avec une sécurité cryptographique.

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Why crypto.getRandomValues() beats Math.random()

Math.random() uses a pseudorandom algorithm that is predictable if the seed is known. crypto.getRandomValues() uses the operating system’s cryptographically secure entropy source, making it truly unpredictable and suitable for security-sensitive applications. Every number on this page is generated with the Web Crypto API.

Guide

Generate random numbers, securely

This tool produces random numbers in several modes: a single value in a range, a set of unique numbers (no repeats), a list that allows duplicates, dice rolls, coin flips, and lottery picks. Crucially, it draws from the browser's Web Crypto API rather than Math.random(), so the results are cryptographically secure rather than predictable.

Pseudorandom vs. truly random

Most everyday random functions are pseudorandom: an algorithm produces a sequence that looks random but is fully determined by a starting seed, so it can in principle be predicted or reproduced. Cryptographically secure generators, like the one this tool uses, gather unpredictable entropy from the operating system, making the output suitable for anything where guessability matters, such as picking a fair winner or generating a token.

Numbers with or without repetition

The distinction matters depending on your task. A dice roll allows repetition, because rolling the same number twice is normal. A raffle draw or lottery needs unique numbers, because the same entry should not be picked twice. This tool offers both, so you can draw a set of distinct winners or a list where duplicates are allowed, as the situation requires.

Common uses

Random numbers drive giveaways and prize draws, sampling and shuffling, games and dice (including polyhedral dice like the d20 used in tabletop role-playing), decision-making coin flips, and quick lottery-style picks. Because each generation is independent and unbiased, every outcome in your chosen range has an equal chance.

Dernière mise à jour: septembre 2026

Frequently Asked Questions

Le tirage est-il équitable ?
Oui, loutil repose sur lAPI Web Crypto pour une vraie imprévisibilité.