UUID Validator & Decoder: Version, Variant, Timestamp

Valid 01a194c6-10c2-722f-85ab-46b651296723

Version 7 Unix Epoch time-based Sortable by time

01a194c610c2 unix_ts_ms

7 ver

22f rand_a

85ab46b651296723 var + rand_b

Version	7 Unix Epoch time-based
Variant	RFC 9562 (formerly RFC 4122 / DCE 1.1) (bits `10`)
Timestamp (UTC)	`2026-11-01T01:42:50.818Z` Unix: 1793497370818 ms. Milliseconds.

Version

7 Unix Epoch time-based

Variant

RFC 9562 (formerly RFC 4122 / DCE 1.1) (bits 10)

Timestamp (UTC)

2026-11-01T01:42:50.818Z
Unix: 1793497370818 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)	`01a194c6-10c2-722f-85ab-46b651296723`
Uppercase	`01A194C6-10C2-722F-85AB-46B651296723`
Microsoft GUID (braces)	`{01A194C6-10C2-722F-85AB-46B651296723}`
URN	`urn:uuid:01a194c6-10c2-722f-85ab-46b651296723`
32 hex digits	`01a194c610c2722f85ab46b651296723`
Base64 (RFC byte order)	`AaGUxhDCci+Fq0a2USlnIw==`
128-bit integer (decimal)	`2168205278993372385213452424491656995`
.NET Guid.ToByteArray() (hex)	`c694a101c2102f7285ab46b651296723`
.NET Guid bytes (Base64)	`xpShAcIQL3KFq0a2USlnIw==`

Standard (lowercase)

01a194c6-10c2-722f-85ab-46b651296723

Uppercase

01A194C6-10C2-722F-85AB-46B651296723

Microsoft GUID (braces)

{01A194C6-10C2-722F-85AB-46B651296723}

URN

urn:uuid:01a194c6-10c2-722f-85ab-46b651296723

32 hex digits

01a194c610c2722f85ab46b651296723

Base64 (RFC byte order)

AaGUxhDCci+Fq0a2USlnIw==

128-bit integer (decimal)

2168205278993372385213452424491656995

.NET Guid.ToByteArray() (hex)

c694a101c2102f7285ab46b651296723

.NET Guid bytes (Base64)

xpShAcIQL3KFq0a2USlnIw==

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 digit	Meaning	Contains a timestamp?
1	Gregorian time-based	Yes (100 ns since 1582)
2	DCE Security	Partial
3	Name-based, MD5	No
4	Random	No
5	Name-based, SHA-1	No
6	Reordered Gregorian time	Yes (100 ns since 1582)
7	Unix Epoch time	Yes (ms since 1970)
8	Custom	Only if your format has one

Variant digit

Binary	Hex digit	Variant
`0xxx`	0 - 7	Reserved, NCS backward compatibility
`10xx`	8 - b	RFC 9562 (the standard variant)
`110x`	c - d	Reserved, Microsoft backward compatibility
`111x`	e - f	Reserved 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.

UUID Validator & Decoder

Valid 01a194c6-10c2-722f-85ab-46b651296723 Copy

Formats

How to decode a UUID

Variant digit

Valid `01a194c6-10c2-722f-85ab-46b651296723`