Generate one or many cryptographically random integers in a range, optionally unique, in your browser.
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- Runs entirely in your browser — nothing is sent to a server
- Generate one or many, optionally unique, from a range
- Free, no account required
How it works
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1
Set the options — length, quantity, character set, or template.
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2
The result generates instantly in your browser.
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3
Regenerate as many times as you like.
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4
Copy the result to your clipboard.
Why use this tool
Every dev utility, one place
Format, convert, encode, decode, and generate — no more juggling ten tabs.
100% private, always
Every tool runs in your browser — your code and data are never sent anywhere.
Works on any device
Runs on Windows, Mac, Linux, iOS, and Android — nothing to install.
Instant results
No queues, no build step — results update as you type.
Built to handle real data
Full Unicode support and RFC-compliant parsing, edge cases included.
Free, always
Free to use, with no rate limits, sign-up, or trial period.
Frequently asked questions
Yes, it uses mathematical randomization techniques that provide an equal probability for every value in your range.
Absolutely, just set the minimum bound to a negative integer to include them in the pool.
It prevents the algorithm from picking the same number twice within a single generated batch.
The bounds are restricted to safe integer limits to prevent floating-point calculation errors.
This utility is specifically built for discrete whole integers, perfect for lotteries or indexing.
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