Validate UUID

Check a hyphenated UUID’s hexadecimal shape, variant bits, and version.

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ToolUUID Validator
Input
Output
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Preview

How it works

The value is lowercased and matched against the 8-4-4-4-12 layout, with version one through seven and variant 8, 9, a, or b accepted. The all-zero nil identifier is handled as a special valid sentinel.

  • The canonical hyphenated text form is interoperable.
  • Version and variant are checked separately from length.

Worked example

Valid UUID v4
Validate a UUID version 4 (random)
Input
											550e8400-e29b-41d4-a716-446655440000
Output
												Valid UUID v4: 550e8400-e29b-41d4-a716-446655440000

When to use this

Database keys, request correlation IDs, and test fixtures validate UUIDs.

Edge cases

  • The nil UUID has zero version and variant bits but is accepted as a sentinel.
  • A 36-character value with the wrong variant nibble is invalid.
  • Uppercase input is normalized to lowercase in the result.

References