UUID Generator
Generate random v4 or time-ordered v7 UUIDs in bulk with formatting options, and validate any UUID to see its version.
Runs in your browser — your data never leaves your deviceUUID validator
v4 or v7?
- v4 — 122 random bits. Unpredictable; the safe default for IDs and tokens.
- v7 — starts with a millisecond timestamp, so IDs sort by creation time. Ideal for database primary keys: fewer index page splits than v4.
How to use UUID Generator
- 1
Pick a version
Choose random v4 or time-ordered v7, which sorts by creation time.
- 2
Set count and format
Generate 1 to 1000 UUIDs, with uppercase, no-hyphen or braces options.
- 3
Copy or download
Copy all UUIDs or save them as a .txt file. Paste any UUID to validate it.
Frequently asked questions
Are these UUIDs truly unique?
They are generated with your browser’s cryptographically secure random number generator. A v4 UUID has 122 random bits — you would need to generate about a billion per second for 85 years to have a 50% chance of a single collision.
What is the difference between UUID v4 and v7?
v4 is fully random. v7 (RFC 9562) begins with a 48-bit Unix millisecond timestamp followed by random bits, so values sort in creation order. That makes v7 a great choice for database primary keys, while v4 reveals nothing about when it was created.
Is a GUID the same as a UUID?
Yes. GUID is Microsoft’s name for the same 128-bit identifier. Use the Uppercase and Braces options to get the {XXXXXXXX-XXXX-...} style often used in Windows, .NET and the registry.
How does the validator detect the version?
The version is the first hex digit of the third group (e.g. xxxxxxxx-xxxx-4xxx-…) and the variant is encoded in the fourth group. For time-based v1, v6 and v7 UUIDs the validator also decodes the embedded creation time.