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Random number generator

Set a range and generate one number or a list. Generation takes place on your device.

Integers from −1,000,000,000,000 to 1,000,000,000,000. Generate 1 to 1000 results at a time.

How are numbers selected?

The browser’s cryptographic random source is used. Selection does not depend on a clock, counter or user-provided seed. Out-of-range values are rejected, so taking a remainder cannot introduce bias.

What does “no repeats” mean?

Each integer in the range can appear once. The number of results cannot exceed the number of available integers. With this option off, repeats are allowed and do not by themselves indicate an error.

Can a result be guessed?

Cryptographic randomness does not enlarge the range: a number from 1 to 10 can still be guessed. Without repeats, fewer options remain after each selection. If a working cryptographic generator is unavailable, no result is produced.

For passwords, use the dedicated tool: Password generator.