About this tool
Generate random UUID v4 and v1 identifiers. Handy for auth debugging, test fixtures, and moving data between transport formats like Base64, URL encoding, and tokens.
Choose UUID v4 (random) or UUID v1 (time-based) in Version. Click Generate. Example — Mint a random v4 id for a fixture: try `Version: UUID v4` and expect something like `3f1a2c8e-9b4d-4e71-a2c3-8d5f6e7a9012`. Each click yields a new value; the sample shows the canonical 8-4-4-4-12 shape.
v1 includes time/node-related bits — do not treat it as secret or privacy-preserving. See also: UUID & ULID Inspector, ULID & Nano ID Generator, and Fake Data Generator. Runs in your browser — nothing you paste gets uploaded.
How to use
- Choose UUID v4 (random) or UUID v1 (time-based) in Version.
- Click Generate.
- Copy the UUID from the output editor via Copy UUID.
- Generate again whenever you need another identifier.
Example
Mint a random v4 id for a fixture
Input
Version: UUID v4
Output
3f1a2c8e-9b4d-4e71-a2c3-8d5f6e7a9012
Each click yields a new value; the sample shows the canonical 8-4-4-4-12 shape.
Limitations
- v1 includes time/node-related bits — do not treat it as secret or privacy-preserving.
- Does not generate ULID, KSUID, or NanoID; use those tools when sortability matters.
- Collision risk is negligible for v4 in normal use, but uniqueness is still not a substitute for DB constraints.
Related guides
1Related tools
3Frequently asked questions
What does the UUID Generator do?
Generate random UUID v4 and v1 identifiers. Runs in your browser — no install, no account.
How do I use the UUID Generator?
Choose UUID v4 (random) or UUID v1 (time-based) in Version. Click Generate. Copy the UUID from the output editor via Copy UUID. Generate again whenever you need another identifier.
Is the UUID Generator free?
Yes. No signup, no usage limits, no paywall.
Does the UUID Generator upload my data?
No. Processing happens locally in JavaScript. Your input is not uploaded, stored, or logged.
What are the limitations of the UUID Generator?
v1 includes time/node-related bits — do not treat it as secret or privacy-preserving. Does not generate ULID, KSUID, or NanoID; use those tools when sortability matters. Collision risk is negligible for v4 in normal use, but uniqueness is still not a substitute for DB constraints.