UUID Validator

Examples

f47ac10b-58cc-4372-a567-0e02b2c3d479

Valid: yes
Version: v4 — random
Variant: RFC 4122 / DCE 1.1
Bytes:   f4 7a c1 0b 58 cc 43 72 a5 67 0e 02 b2 c3 d4 79

018e7c3a-4f3b-7a8c-9e2d-1f3a2b4c5d6e

Valid: yes
Version: v7 — time-ordered
Variant: RFC 4122 / DCE 1.1
Timestamp: 2024-03-05T13:38:22.587Z

{F47AC10B-58CC-4372-A567-0E02B2C3D479}

Valid: yes
Normalized: f47ac10b-58cc-4372-a567-0e02b2c3d479
Version: v4 — random
Variant: RFC 4122 / DCE 1.1

00000000-0000-0000-0000-000000000000

Valid: yes
Version: Nil UUID (all zeros)
Often used as a sentinel / "no value" placeholder.

g47ac10b-58cc-4372-a567-0e02b2c3d479

Valid: no
Error: Not a valid UUID format. Expected 32 hex digits with hyphens at positions 8-4-4-4-12.

Frequently Asked Questions

What does this validator check?

It checks that the input matches the canonical UUID format (8-4-4-4-12 hex digits with hyphens), then decodes the version nibble (byte 6, high nibble) and the variant bits (byte 8). For v1 and v7 UUIDs it also extracts the embedded timestamp and converts it to a human-readable ISO 8601 date.

What input formats are accepted?

Canonical (f47ac10b-58cc-4372-a567-0e02b2c3d479), uppercase, braced GUIDs ({...}), and URN form (urn:uuid:...). The validator strips wrappers and normalizes case before checking.

What's the difference between version and variant?

Version (1-8) tells you how the UUID was generated — time-based, random, name-hashed, or time-ordered. Variant tells you which UUID specification family the bits follow: RFC 4122 (the modern standard), NCS (legacy), Microsoft (GUID), or reserved for future use. The variant is encoded in the top bits of the 17th hex digit (byte 8).

Why does my UUID say 'invalid version'?

The version nibble must be 1-8. If you see 0, the most likely cause is that you're looking at the nil UUID (all zeros) or a malformed value. If you see a value above 8, the UUID may have been corrupted in transit, or it follows a non-standard scheme.

Are timestamps reliable for v1 / v7?

Yes — v1 encodes 100-nanosecond intervals since 1582-10-15 UTC, and v7 encodes Unix epoch milliseconds. Both are decoded directly from the UUID bits with no inference, so the displayed timestamp is exactly what the generator wrote.

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