UUIDTools.com

UUID Validator & Decoder

Paste a UUID or GUID to check it and see what is inside: version, variant, timestamp and more.

Accepts hyphenated, 32 hex digits, {braces}, urn:uuid:, any case. Try a fresh v7.

Valid 01a1e076-4857-730d-be78-3bc105c07f42

Version 7 Unix Epoch time-based Sortable by time
01a1e0764857 unix_ts_ms
7 ver
30d rand_a
be783bc105c07f42 var + rand_b
Version7 Unix Epoch time-based
VariantRFC 9562 (formerly RFC 4122 / DCE 1.1) (bits 10)
Timestamp (UTC)2026-11-15T18:26:50.583Z
Unix: 1794767210583 ms. Milliseconds.

Version 7 UUIDs start with a 48-bit Unix timestamp in milliseconds followed by random bits, so they sort by creation time.

Formats

Standard (lowercase) 01a1e076-4857-730d-be78-3bc105c07f42
Uppercase 01A1E076-4857-730D-BE78-3BC105C07F42
Microsoft GUID (braces) {01A1E076-4857-730D-BE78-3BC105C07F42}
URN urn:uuid:01a1e076-4857-730d-be78-3bc105c07f42
32 hex digits 01a1e0764857730dbe783bc105c07f42
Base64 (RFC byte order) AaHgdkhXcw2+eDvBBcB/Qg==
128-bit integer (decimal) 2169740421072058357585323410189221698
.NET Guid.ToByteArray() (hex) 76e0a10157480d73be783bc105c07f42
.NET Guid bytes (Base64) duChAVdIDXO+eDvBBcB/Qg==

API: /api/decode/01a1e076-4857-730d-be78-3bc105c07f42

How to decode a UUID

Every RFC 9562 UUID stores its version in the 13th hex digit and its variant in the top bits of the 17th digit:

xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx
             M = version (1-8)   N = variant (8, 9, a, b = RFC 9562)
Version digitMeaningContains a timestamp?
1Gregorian time-basedYes (100 ns since 1582)
2DCE SecurityPartial
3Name-based, MD5No
4RandomNo
5Name-based, SHA-1No
6Reordered Gregorian timeYes (100 ns since 1582)
7Unix Epoch timeYes (ms since 1970)
8CustomOnly if your format has one

Variant digit

BinaryHex digitVariant
0xxx0 - 7Reserved, NCS backward compatibility
10xx8 - bRFC 9562 (the standard variant)
110xc - dReserved, Microsoft backward compatibility
111xe - fReserved for future definition

The decoder never throws on odd input: unknown versions, legacy variants and the special nil (00000000-…) and max (ffffffff-…) UUIDs all produce a readable result.

Learn more in UUID versions explained.