UUID Structure Decoder & Byte Inspector
Local ProcessingInspect internal version bits, RFC variant specification, and 16 raw byte values of any UUID.
How It Works & Processing Standards
Inspect internal version bits, RFC variant specification, and 16 raw byte values of any UUID.
Tool processing runs in your browser. If you create a calculator or conversion share link, its values are included in the URL. See the privacy policy for account, analytics and advertising data.
Current Limits
- Maximum input length: 100,000 characters
The 13th hex digit of a UUID is its version and the 17th its variant. This tool reads them to tell you how the UUID was made, or just checks the format when you pick that task.
What You Can Do
- Decode
- Shows version, variant and the 16 bytes.
- Format check
- Checks for an 8-4-4-4-12 hexadecimal UUID.
How to Use UUID Structure Decoder & Byte Inspector
- 1Choose a taskDecode or format check.
- 2Paste a UUIDPaste a UUID with hyphens.
- 3Read the resultSee version, variant and bytes, or validity.
Examples
Decode the DNS namespace UUID
Input: 6ba7b810-9dad-11d1-80b4-00c04fd430c8
Result: Version v1, variant RFC 9562, bytes 6b a7 b8 10 9d ad 11 d1 80 b4 00 c0 4f d4 30 c8
A string that is not a UUID
Input: not-a-uuid
Result: ✗ Valid: no
Common Use Cases
- Telling whether a logged ID is time-based (v1, v7) or random (v4)
- Validating UUIDs received from another system
- Working with a UUID as a byte array
Frequently Asked Questions (FAQ)
Can I tell the version just by looking?
Yes. The first character of the third group is the version: 11d1 means v1, a group starting with 4 is v4 and one starting with 7 is v7.