UUID Validator
Check canonical, URN, or braced UUID strings against RFC 9562 version and variant rules.
Separate values with whitespace or commas. Canonical UUID strings, urn:uuid: values, and braced strings are recognized.
Validation Result
Validation details will appear here.
Format check only
Validation reads the UUID text and its version/variant bits. It does not query a database or prove that the identifier exists, is unique, or belongs to a particular record.
Reserved forms need context
A canonical 8-4-4-4-12 string can still use a non-RFC variant or a version nibble reserved for future definition. The result reports that distinction instead of calling every UUID-shaped string valid.
UUID shape, variant, and version are separate questions
RFC 9562 defines the familiar UUID text as 32 hexadecimal digits grouped 8-4-4-4-12. That shape alone does not tell you how the 128 bits should be interpreted. The variant bits choose the layout family, and only the RFC 10xx variant uses the version table that includes UUIDv1 through UUIDv8.
This validator therefore avoids the old shortcut of accepting only versions 1 through 5. RFC 9562 added UUIDv6, UUIDv7, and UUIDv8, while also defining Nil and Max as special UUID values.
How each result is classified
- Defined RFC 9562 UUID: canonical hexadecimal text, RFC variant bits, and a fully specified version such as 1, 3, 4, 5, 6, 7, or 8.
- DCE Security UUIDv2 form: the version and variant bits identify v2, whose full definition RFC 9562 leaves outside its scope.
- Defined special UUID: the all-zero Nil UUID or all-one Max UUID.
- Reserved/non-RFC form: UUID-shaped text using another variant or an unused/reserved RFC-version nibble.
- Invalid UUID text: the hexadecimal groups or separators do not match the UUID string representation.
URNs and braces are presentation wrappers
RFC 9562 shows the urn:uuid: form for UUID URNs and notes that some implementations display the hexadecimal UUID inside curly braces. The validator removes one recognized wrapper before checking the underlying 128-bit textual form and reports which presentation it received.
Version numbers do not prove semantics by themselves
Seeing a 7 in the version position means the bits claim UUIDv7 only when the UUID also uses the RFC variant. This page checks those fixed fields, but it does not reconstruct every version-specific timestamp, namespace, hash input, counter, or custom UUIDv8 layout. A value can pass the structural checks while still having been produced incorrectly by its original generator.
Current specification
RFC 9562 replaced RFC 4122 and is the reference used here for the string form, variants, versions 1–8, Nil UUID, and Max UUID.