Random numbers
Numbers, dice, lottery picks and coin flips from your browser's Web Crypto API. Everything runs locally, nothing is sent to a server.
Nothing drawn yet.
Where the randomness comes from
The generator uses crypto.getRandomValues() from the Web Crypto API. Unlike Math.random(), a deterministic pseudo-random generator, the Crypto API draws on entropy from your operating system.
That makes the numbers suitable for lottery picks, draws and other cases where nobody should be able to predict the result, even if they know exactly when it was generated.
Whole numbers are drawn with Math.floor(random * (max - min + 1)) + min, so every value in the range is equally likely. Decimals use random * (max - min) + min, a continuous uniform distribution.
Do the numbers leave the browser?
No. Everything is calculated locally, no request goes to a server. The history only lives in this tab and is gone when you reload.
Frequently Asked Questions
- How does the random number generator work?
- The generator uses the browser's cryptographically secure crypto.getRandomValues() API to produce true random numbers. This method is more secure than standard pseudo-random number generators.
- Are the generated numbers truly random?
- Yes. A cryptographically secure pseudo-random number generator (CSPRNG) is used, which draws entropy from the operating system. The results are not predictable.
- Can I generate multiple random numbers at once?
- Yes, you can generate up to 100 numbers at once. With the 'No duplicates' option every value appears only once.
- Does the generator support decimals and negative numbers?
- Yes, you can enter both decimal and negative numbers as minimum and maximum values. The generator automatically adapts the result to your chosen range.
- Can I export the history of generated numbers?
- Yes, you can export the history as a CSV file. Click 'As CSV' in the history section. The file includes timestamps and drawn values, including dice, lottery picks and coin flips.