UUID Validator Online
Validate a UUID or GUID online. Check the 8-4-4-4-12 shape, version nibble and RFC variant, including the Nil UUID.
Part of the free UUID Generator. Runs in your browser — nothing is uploaded.
UUID Validator Online
A valid UUID is 32 hex digits in 8-4-4-4-12 groups. The validator also reads the version and variant bits so you can tell a random v4 from a time-ordered v7 or a Nil UUID.
Worked example: A truncated value fails validation
UUID
550e8400-e29b-41d4-a716-44665544000
Validator result
✗ Not a valid UUID 550e8400-e29b-41d4-a716-44665544000
Practical tip
Accept both uppercase and lowercase hex, and optional braces. Reject everything else — including IDs missing a single digit.
How to use this UUID Generator
- 1Use the live tool above — it runs entirely in your browser and never uploads your data.
- 2Paste the sample from the worked example, or use your own input.
- 3Copy the result, then adapt the same steps in your editor, script, or pipeline.
UUID Validator Online FAQs
Does a valid format mean the UUID exists?
No. Validation only checks shape and reserved bits. Anyone can invent a well-formed UUID.
Are uppercase UUIDs valid?
Yes. Hex is case-insensitive. 550E8400-E29B-41D4-A716-446655440000 is the same ID as the lowercase form.
More UUID Generator pages
- UUID v4 Generator OnlineGenerate random UUID v4 values online. Cryptographically secure, RFC 4122 / RFC 9562 compatible, free and private in your browser.
- UUID v7 GeneratorGenerate time-ordered UUID v7 values (RFC 9562). Better as database primary keys than random UUID v4 because they sort by creation time.
- GUID Generator OnlineGenerate a GUID online in the Windows {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX} format or as a plain UUID. Free, no signup.
- Generate a UUID Without HyphensGet a UUID as 32 hex characters with no hyphens. Useful for filenames, tokens and systems that reject the dashed format.
- Bulk UUID GeneratorGenerate many UUIDs at once — up to 1,000 UUID v4 or v7 values. Copy or download the list. Free and browser-based.
- The Nil UUID ExplainedThe Nil UUID is 00000000-0000-0000-0000-000000000000. See when to use it, how validators treat it, and why it is not a random ID.
- Uppercase GUID GeneratorGenerate an uppercase GUID / UUID. Some Windows APIs and .NET codebases expect hex A–F instead of a–f.
- UUIDs as Database Primary KeysShould you use UUID v4 or UUID v7 as a primary key? See how each version affects index locality, and generate sample keys.
- UUID vs GUIDUUID and GUID are the same 128-bit identifier. Learn the naming, formatting differences and how to convert between them.