UUID Generator

Generate random v4 or time-ordered v7 UUIDs in bulk, with formatting options and one-click copy.

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What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit value like 550e8400-e29b-41d4-a716-446655440000. Databases, APIs, and distributed systems use them as IDs that don't need a central counter to stay unique.

v4 vs. v7

v4 is purely random — the classic choice. v7 (newer, RFC 9562) embeds the current timestamp in the first bits, so IDs generated later sort after earlier ones. That ordering makes v7 much kinder to database indexes when UUIDs are primary keys.

FAQ

What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit value written as 32 hexadecimal digits in five groups, e.g. 550e8400-e29b-41d4-a716-446655440000. It identifies records without a central registry.
UUID v4 vs v7 — which should I use?
Use v4 for purely random IDs. Use v7 when IDs are a database primary key: v7 embeds a timestamp so new rows sort together, which is much friendlier to B-tree indexes.
Are UUIDs guaranteed to be unique?
Not mathematically guaranteed, but a v4 collision is so unlikely you can ignore it — you would need to generate about a billion UUIDs per second for 85 years to reach a 50% chance of one collision.
Is it safe to generate IDs in the browser?
Yes. This tool uses the Web Crypto API (crypto.getRandomValues), which is cryptographically secure randomness — the same quality a server would use.
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