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How to use UUID v5 Generator

Choose a namespace (DNS, URL, OID, X.500 or a custom UUID) and enter a name. The tool SHA-1 hashes them to produce a stable version 5 UUID that never changes for that input.

Frequently asked questions

How is v5 different from v4?

v4 UUIDs are random; v5 UUIDs are deterministic — the same namespace and name always yield the same UUID, ideal for reproducible IDs.

What is a namespace?

A base UUID identifying the context (like DNS or URL). Combining it with a name prevents collisions between different kinds of inputs.

When should I use v5?

When you need a stable identifier derived from existing data, such as generating a consistent ID for a URL or username.

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