Random Number Generator – Free Online

Regular random numbers use Math.random() which is a pseudo-random number generator (PRNG). It is fast and fine for games, simulations and most uses, but its output is technically predictable given its seed state. Crypto-secure mode uses window.crypto.getRandomValues() which draws from the operating system's entropy pool (hardware events, timing jitter). This is unpredictable even by the computer itself and is suitable for security-sensitive applications like generating keys, tokens or secure PIN codes.

Unique mode ensures the same number cannot appear twice in a single generation. It works by generating a shuffled array of numbers in your range and picking from it. Note: if you request more numbers than exist in your range (e.g. 10 unique numbers between 1 and 5), the tool alerts you and reduces the count to the available range size. This is perfect for lottery draws, raffle systems, and random team assignments.

The lottery preset generates 6 unique random numbers between 1 and 49, sorted in ascending order — matching the format of most 6/49 lottery games. Numbers are guaranteed to be unique (no repeats) and are generated using crypto-secure randomness for true unpredictability. Each draw is completely independent of previous draws.

Yes. Set the Minimum value to a negative number (e.g. -100) and the Maximum to any value greater than the minimum (e.g. 100). The generator will produce numbers anywhere in that range including zero, negative and positive values. This is useful for simulations, statistical sampling and games that use negative scoring.