UUID Variant A – Validate Hexadecimal A Variant Nibble

Local only

Show that hexadecimal A is accepted by the current UUID variant check without changing UUID version detection.

36 chars · 1 line

Waiting for input

Valid UUID v4

UUID variant inspection

Is hexadecimal A valid in the UUID variant position?

Yes for the current inspector. A canonical UUID with the first digit of the fourth group set to hexadecimal A falls inside VetaTool's accepted 8-through-B RFC-compatible variant range. 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. Read the first hexadecimal digit in the fourth UUID group.
  2. Interpret A as decimal 10 for the validator's numeric range check.
  3. Keep UUID version interpretation separate from variant interpretation.

Hexadecimal letters are part of UUID bit fields

The canonical UUID pattern is case-insensitive hexadecimal, so A is a normal hexadecimal digit rather than special syntax.

In the current inspector, A is converted to decimal 10 and falls within the accepted variant range from 8 through 11.

Variant nibble A example

The fourth group begins with hexadecimal A.

UUID input

550e8400-e29b-41d4-a716-446655440000

Validation result

Valid UUID v4

Common questions

Frequently asked questions

Is lowercase a also accepted?

Yes. The UUID format pattern is case-insensitive, and hexadecimal parsing treats A and a equivalently.

Why is this still version 4?

The version nibble is the first digit of the third group. The variant nibble is read separately from the fourth group.

Recommended next steps

UUID RFC Variant 9Confirm that a fourth-group nibble of 9 remains inside the accepted RFC-compatible variant range.UUID RFC Variant BInspect the upper accepted boundary of the validator's RFC-compatible variant nibble range.UUID Generator & Validator OnlineGenerate UUID v4 batches or validate canonical UUID format, version, and variant locally.

Debugging a specific UUID issue? Browse UUID troubleshooting.