Generate UUIDs in your browser: cryptographically random v4 or time-ordered, sortable v7. Bulk generation up to 25 at once, uppercase and no-hyphen options.
How UUIDs are generated
A UUID is a 128-bit identifier written as 36 characters. Version 4 fills 122 bits with cryptographically secure random data from your browser's crypto API. Version 7 puts a millisecond timestamp in the first 48 bits and random data in the rest, so ids sort by creation time — ideal for database primary keys where insert order matters.
crypto.randomUUID() → xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxxFrequently asked questions
Can two UUIDs collide?
In practice, no. A v4 UUID has 122 random bits — you would need to generate about 2⁶¹ ids (billions per second for decades) before a collision becomes likely. Treat them as unique.
Should I use v4 or v7?
v4 when ids should reveal nothing — it is pure randomness. v7 when ids are database keys: the leading timestamp keeps them roughly sequential, which keeps B-tree indexes fast and rows naturally ordered by creation time. Note that v7 exposes the creation moment.
Are these UUIDs generated locally?
Yes. They come from your browser's crypto.randomUUID and getRandomValues APIs — cryptographically secure random generators. Nothing is fetched from or sent to a server.
Last updated: 7 July 2026
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Runs entirely in your browser — nothing you enter is uploaded. DevMint · MintKit