Random Number Generator
Generate random numbers with custom range, quantity, deduplication. Cryptographically secure
About Random Number Generator
This tool uses the browser's built-in cryptographically secure random number generator (crypto.getRandomValues) to produce high-quality random numbers. Supports custom value range, quantity, integer/decimal, step increment, and more to meet various random number needs.
This tool uses the browser's built-in cryptographically secure random number generator (crypto.getRandomValues), supporting custom range, quantity, deduplication, and sorting for lottery, sampling, and testing scenarios.
Use Cases
The random number generator is suitable for the following scenarios:
- Lottery/Raffle：Generate unique random numbers for lotteries and raffles
- Random Sampling：Randomly sample from datasets for statistical analysis
- Test Data：Generate random test data for software development and testing
- Education：For probability statistics teaching and randomness concept demonstration
FAQ
Are the generated numbers truly random?
Browsers use crypto.getRandomValues() which is based on the operating system's cryptographically secure random source (e.g., /dev/urandom on Linux). The generated numbers have extremely high unpredictability, sufficient for most applications.
How is no-duplicates guaranteed?
When "No Duplicates" is enabled, the tool tracks generated values to ensure each number appears only once. If there aren't enough unique values in the specified range, a warning is shown.
Can I generate even numbers or specific steps?
Yes. Set "Step/Increment" in advanced options. For example, setting it to 2 generates only even numbers, setting it to 5 generates multiples of 5.
Is data uploaded to a server?
No. All random numbers are generated locally in your browser and never sent to any server.