UUID Generator
Generate random UUIDs in bulk, ready to copy.
The identifiers are generated in your browser and are never sent anywhere, so nobody else has seen the ones you copy.
Every identifier on this page comes from the cryptographic random source in your browser, the same one that backs keys and session tokens. They are version 4 UUIDs, the kind whose 122 random bits are the whole of their content: no timestamp, no MAC address, no counter, nothing that says where or when they were made. Five are waiting when the page loads, and a fresh batch is one press away.
More about UUID Generator
Ask for up to a thousand at a time. The output is plain text, one identifier per line, ready to paste into a seed file, a test fixture or a spreadsheet column, or to download as a text file. Uppercase and hyphen-free forms are there for the systems that expect them, such as Microsoft-style GUIDs and columns that store the value as 32 hex characters, and your choice is remembered the next time you open the page.
Version 4 is the sensible default for most work: primary keys, request ids, idempotency keys, anything that has to be unique without a central allocator handing numbers out. If you need identifiers that sort by the time they were created, version 7 is the one to look for, and this tool does not generate it.
- Version 4 UUIDs drawn from the browser cryptographic random source
- Generate anywhere from one to a thousand at a time
- Uppercase output for the systems that expect it
- Hyphens optional, for the 32-character form
- One identifier per line, ready to paste straight into a file
- Copy the whole batch or download it as a text file
- Your case and hyphen choices are remembered for next time
How to use it
- 1Set how many identifiers you need, from one up to a thousand.
- 2Turn uppercase or hyphens on or off to match the format your system expects.
- 3Press Generate to replace the list with a fresh batch.
- 4Read the result in the output panel, one identifier per line.
- 5Copy the whole batch, or download it as a text file.
Questions
Are these UUIDs generated on a server?
No. They are produced in your browser by the same cryptographic random source used for keys and tokens, and the values are never sent anywhere.
Which UUID version is this?
Version 4, which is random apart from the six bits that record the version and the variant. Version 1 and version 7 are not generated here.
Can two of them collide?
A version 4 UUID carries 122 random bits, so collisions are not something you will meet in practice. You would need to generate billions before the odds became worth thinking about.
Is a UUID a secret?
It is unpredictable, so a version 4 UUID works as an unguessable identifier in a URL. It is not a substitute for an access token, because it carries no expiry, no scope and no way to revoke it.
Why do some systems want them without hyphens?
Fixed-width storage such as a 32-character column, or a compact key format, has no room for the separators. Turn hyphens off and the same value comes out in that form.