How random numbers are generated
Each number is drawn from your inclusive minimum-to-maximum range using crypto.getRandomValues and rejection sampling, which removes the modulo bias that simpler methods introduce. With unique mode on, drawn values are tracked so no number repeats, which is ideal for raffles or random sampling without replacement.
Frequently asked questions
How does the random number generator work?
It uses your browser's cryptographically secure random source and rejection sampling to pick whole numbers with no modulo bias, so every value is equally likely.
Can I generate numbers with no duplicates?
Yes. Turn on unique values for raffles or sampling. The count cannot exceed the size of the range.
Are the minimum and maximum included?
Yes. The range is inclusive, so both the minimum and maximum can be drawn.
Is this random enough for a giveaway?
For casual contests it is excellent thanks to crypto-grade randomness. Regulated lotteries must follow their own certified systems.
Is anything stored or sent to a server?
No. Numbers are generated entirely in your browser and never uploaded or saved.
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Disclaimer: This generator is intended for casual and general-purpose use. It is not a certified system for regulated gambling or official lottery draws.