UUID Generator
Generate cryptographically random UUID v4 in bulk. Uppercase and hyphenless options.
About this tool
This UUID generator produces UUIDs (v4) β unique identifiers that are extremely unlikely to collide β in batches. They shine whenever you need an ID that will not clash with others: database primary keys, API request IDs, file names, or identifiers for test data. Specify how many you need and generate several at once.
It generates UUID version 4, which builds most of the value from random numbers. It uses a cryptographically secure random source (the browser's crypto feature), so the values are harder to predict than simple pseudo-random numbers and more reliable as IDs. In practice you can use them without worrying about collisions.
Output options let you uppercase the letters or remove the hyphens. The hyphen-free form is handy for uses where you do not want separator characters, such as file names or tokens. Generated UUIDs are ready to copy and use.
Everything runs in your browser, so the generated values are never sent to a server. The random numbers are produced on your device as well, so there is no external dependency and you can prepare exactly as many IDs as you need on the spot. It is easy to use across development, testing, and documentation.
How to use
- Set the count, and optionally uppercase or hyphenless.
- Press Regenerate for new UUIDs and copy them individually or all at once.
FAQ
What is UUID v4?
A UUID whose value is mostly built from random numbers. Its high randomness makes collisions effectively unlikely, so it is widely used where a unique identifier is needed, such as database primary keys and request IDs.
How secure are the generated values?
They are generated using a cryptographically secure random source (the browser's crypto feature). Because they are harder to predict than simple pseudo-random numbers, they are more reliable as IDs.
Can I generate several at once?
Yes. Specify how many you need and generate them in a batch β handy when you want a lot of IDs for test data.
Can I get uppercase or hyphen-free forms?
Yes. Output options let you uppercase the letters or remove the hyphens, which suits file names or tokens where you do not want separator characters.
Are the generated UUIDs sent to a server?
No. Both generation and the random source run entirely in your browser (on your device), and the values are never sent externally.
Are they really guaranteed unique?
In theory the chance of a collision is not exactly zero, but the random space is so vast that in practice you can use them without worry. For systems where strict uniqueness is an absolute requirement, pairing them with a database unique constraint adds peace of mind.