Uppercase UUID – Are Capital Hex Letters Valid?

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Show that uppercase hexadecimal UUID text remains valid when the canonical layout and bit fields are correct.

36 chars · 1 line

Waiting for input

Valid UUID v4

UUID character case

Are uppercase UUIDs valid?

Yes. VetaTool's canonical UUID matcher is case-insensitive for hexadecimal A-F, so an uppercase UUID with valid version and variant bits is accepted exactly like its lowercase form. The example is detected as UUID v4. This tool is free to use. No account or payment is required.

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What you can do here

  • Canonical 8-4-4-4-12 UUID validation
  • UUID version inspection
  • RFC 4122 variant checking
  • Nil UUID recognition
  • Uppercase hexadecimal support
  • Browser-local validation

Steps

  1. Paste the uppercase UUID in canonical layout.
  2. Confirm the validator accepts A-F in either case.
  3. Compare identifiers case-insensitively only when that matches your storage and application rules.

Hexadecimal case does not change the UUID bits

Uppercase A-F and lowercase a-f represent the same hexadecimal values. VetaTool therefore preserves validity and version detection across casing differences while still requiring canonical hyphen placement.

Uppercase UUID example

The capital hexadecimal characters still encode a valid UUID v4.

UUID input

550E8400-E29B-41D4-A716-446655440000

Validation result

Valid UUID v4

Common questions

Frequently asked questions

Does UUID case change its value?

No. Uppercase and lowercase hexadecimal characters encode the same UUID bits.

Will uppercase fix an otherwise invalid UUID?

No. Hyphen layout, hexadecimal content, version, and variant still need to be valid.

Recommended next steps

UUID Version DetectionRead the version nibble from a canonical UUID and identify values such as UUID v1.UUID Missing HyphensSee why a 32-hex-character value without canonical hyphens is rejected.UUID Generator & Validator OnlineGenerate UUID v4 batches or validate canonical UUID format, version, and variant locally.

Debugging a specific UUID issue? Browse UUID troubleshooting.