UUID Validator
Validate one or many UUIDs and identify their version (v1–v5) and variant. Paste a list to check each line. Fast, free and 100% client-side.
Last reviewed by the Radiatus Cloud team
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Validate UUIDs and find their version
A UUID is a 128-bit identifier with a specific format, and validating one, and identifying which version it is, is a common need. This tool validates one or many UUIDs and identifies their version and variant, so you can confirm identifiers are well-formed.
Why version matters
A UUID has a defined structure, and its version, encoded in the value, tells you how it was generated: version 4 is random, version 1 is time-based, version 5 is name-based, and so on. Validating that a UUID is well-formed catches typos and malformed identifiers, and knowing the version tells you its properties, whether it is random and unguessable, or derived from a timestamp and therefore partly predictable. Being able to check many at once suits validating a batch. This matters wherever UUIDs are used as identifiers or, sometimes, mistakenly as secrets.
Well-formed identifiers
It runs entirely in your browser, so nothing you paste is uploaded and the result is yours to copy straight into a project. Because it works client-side, you can use it on private code and data without anything leaving your machine.
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Frequently Asked Questions
What does the validator check?
That a UUID is well-formed and, from its value, which version (1 to 5) and variant it is, so you know how it was generated.
Why does the UUID version matter?
Because it tells you the properties: version 4 is random and unguessable, while version 1 is time-based and partly predictable, which matters if used as a secret.
Can it check many at once?
Yes. It validates one or many UUIDs, which suits confirming a whole batch of identifiers.
What does validation catch?
Typos and malformed identifiers that are not valid UUIDs, before they cause problems downstream.
Is my input uploaded?
No. The validation runs entirely in your browser.
Privacy & Security
All processing happens locally in your browser — nothing is uploaded.
How to Use
Paste one or more UUIDs (one per line) to validate each and detect its version.
Disclaimer: This tool is provided "as is" without warranty of any kind. Results are for educational and utility purposes.
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