Random Number Generator
Generate cryptographically secure random numbers within any custom range.
About This Tool
The TulQR Random Number Generator uses the Web Crypto API's crypto.getRandomValues() function, which provides cryptographically secure randomness — far better than Math.random(). You can generate a single number or up to 1,000 at once, with or without duplicates.
Why Random Numbers Matter
Random numbers are at the core of many everyday activities: board games, lotteries, sampling, statistical simulations, security keys, and fair selection processes. But not all random number generators are equal.
Most simple tools use pseudorandom algorithms based on a seed — they look random but are deterministic and can be predicted with enough information. Our tool uses cryptographic randomness from your device's hardware entropy source, via the browser's built-in crypto.getRandomValues() API. This provides unpredictable, uniformly distributed numbers suitable for security-sensitive uses.
The "no duplicates" option uses a cryptographically secure Fisher-Yates shuffle to select unique values from the range, ensuring each number appears at most once — perfect for lottery draws, random sampling, or assigning unique IDs.
You can generate up to 1,000 numbers at once. All generation happens in your browser — no data leaves your device.
Frequently Asked Questions
Is this truly random?
It uses the browser's crypto.getRandomValues() API, which draws from the operating system's entropy pool (hardware events, timing jitter, etc.). This is cryptographically secure randomness, not pseudorandom.
Can I generate negative numbers?
Yes — set Min to a negative value like -100 and Max to 0 or any positive number.
What does 'no duplicates' mean?
When enabled, every number in the output is unique. Useful for drawing lottery numbers or creating a random ordering of items.
What's the maximum range?
You can use any integers your browser can handle as JavaScript numbers (up to ±2^53). The count per generation is capped at 1,000.