UUID generator (v4)
Generate 1 to 1,000 random version 4 UUIDs at once. Switch to uppercase, remove hyphens or wrap them in braces.
Creates version 4 (random) UUIDs with the browser's cryptographic random number generator (Web Crypto). Changing the format keeps the same UUIDs.
1 to 1,000
How to use
- Enter how many UUIDs you need (1 to 1,000).
- Choose options if needed: "Uppercase", "Hyphens" and "Wrap in { }".
- Press "Generate" or one of the quick count buttons (1, 5, 10, 25, 50, 100). Five UUIDs are already generated when the page opens.
- Changing the format options after generating keeps the same UUIDs and only changes how they are written.
- Use "Copy all" or "Download" (.txt).
Notes and limits
- Up to 1,000 UUIDs per run.
- Version 4 (random) only. Time-ordered versions such as v7 are not supported.
- Generated UUIDs are not saved. They are gone when you close the page.
How it works
UUIDs come from the browser's crypto.randomUUID(). Where that is unavailable, 16 random bytes from crypto.getRandomValues() are used and the version (4) and variant bits are set. Math.random is never used.
A v4 UUID has 122 random bits, so an accidental duplicate is extremely unlikely in practice. Uniqueness is not guaranteed, though.
FAQ
Is a GUID the same as a UUID?
Essentially yes. GUID is Microsoft's name for the same format. Use the braces option if you need the {…} form.
Can I use a UUID as a password or secret token?
They are made from cryptographic randomness, but UUIDs are designed as identifiers. For secrets, use a random string of a length suited to the purpose.
Are the generated UUIDs logged?
No. They are generated in your browser and never sent or stored.
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