About Random Number Generation

This generator uses your browser's built-in cryptographic random number generator (crypto.getRandomValues when available, Math.random as fallback) to produce numbers within your specified range.

Common Uses

• Games and lotteries -- dice rolls, card draws, raffle picks
• Decision making -- randomly assign tasks, pick a restaurant, settle a debate
• Education -- probability experiments, statistics homework, random sampling
• Programming -- test data generation, randomized algorithms, load testing

Unique vs. Non-Unique Numbers

When "unique numbers" is enabled, no number will repeat in the output. This is useful for lottery-style draws or when you need to randomly select distinct items from a set. Note that if you request more unique numbers than exist in your range (e.g., 20 unique numbers between 1 and 10), only as many as possible will be generated.

True Randomness vs. Pseudo-Randomness

Computers generate pseudo-random numbers using deterministic algorithms seeded with entropy sources. For most everyday purposes -- games, sampling, decision making -- this is indistinguishable from true randomness. For cryptographic applications, browsers use hardware entropy sources that produce numbers secure enough for encryption keys.