Random Number Generator.
Set your range and count — get cryptographically random results instantly.
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Click Generate
What is a random number generator?
A random number generator produces numbers with no discernible pattern — each number in the range is equally likely. True randomness has applications across gaming, statistics, cryptography, education, and decision-making. This tool uses the browser's cryptographic random API to generate high-quality random numbers with no predictable sequence.
Capabilities
What You Get
Backed by the browser's crypto API rather than Math.random, so results are suitable for draws and sampling.
Cryptographic Source
Uses the Web Crypto API rather than the predictable Math.random.
Any Range
Set your own minimum and maximum bounds for the draw.
Bulk Generation
Produce many numbers at once instead of rolling repeatedly.
Unique Mode
Exclude repeats when drawing winners or sampling without replacement.
One-Click Copy
Copy the whole result set straight to the clipboard.
No Seed Stored
Nothing about your draws is recorded, logged, or transmitted.
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FAQ
Random Number Generator FAQ.
How are the random numbers generated?
The tool uses the browser's crypto.getRandomValues() API, which generates cryptographically secure pseudorandom numbers using the operating system's entropy pool. This is much higher quality than Math.random().
What is the maximum number of values I can generate?
You can generate up to 500 numbers at once. For larger batches, generate multiple sets and combine them.
How does the 'Unique only' option work?
With unique mode on, each generated number can only appear once in the result set. The range must be large enough to contain the requested count of unique integers.
Can I generate decimal numbers?
Yes. Toggle 'Decimals' on and the generator will produce numbers with up to 4 decimal places within your specified range. The min and max values can also be decimals.
Is a random number between 1 and 10 truly uniform?
Yes. The generator maps the random bytes to your range using floating-point arithmetic, ensuring all values in the range are equally likely. Edge values (min and max) are included.
What is the difference between random and pseudorandom?
True randomness requires a physical entropy source (atmospheric noise, radioactive decay). Pseudorandom numbers are generated by algorithms that produce sequences indistinguishable from random for practical purposes. The crypto API uses the OS entropy pool, making it suitable for security-sensitive uses.
