UUID Validator & Decoder: Version, Variant, Timestamp

Valid 01a16e4f-82d6-726c-8d76-8de585d40107

Version 7 Unix Epoch time-based Sortable by time

01a16e4f82d6 unix_ts_ms

7 ver

26c rand_a

8d768de585d40107 var + rand_b

Version	7 Unix Epoch time-based
Variant	RFC 9562 (formerly RFC 4122 / DCE 1.1) (bits `10`)
Timestamp (UTC)	`2026-10-24T14:27:47.030Z` Unix: 1792852067030 ms. Milliseconds.

Version

7 Unix Epoch time-based

Variant

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

Timestamp (UTC)

2026-10-24T14:27:47.030Z
Unix: 1792852067030 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)	`01a16e4f-82d6-726c-8d76-8de585d40107`
Uppercase	`01A16E4F-82D6-726C-8D76-8DE585D40107`
Microsoft GUID (braces)	`{01A16E4F-82D6-726C-8D76-8DE585D40107}`
URN	`urn:uuid:01a16e4f-82d6-726c-8d76-8de585d40107`
32 hex digits	`01a16e4f82d6726c8d768de585d40107`
Base64 (RFC byte order)	`AaFuT4LWcmyNdo3lhdQBBw==`
128-bit integer (decimal)	`2167425154582565186119808558224900359`
.NET Guid.ToByteArray() (hex)	`4f6ea101d6826c728d768de585d40107`
.NET Guid bytes (Base64)	`T26hAdaCbHKNdo3lhdQBBw==`

Standard (lowercase)

01a16e4f-82d6-726c-8d76-8de585d40107

Uppercase

01A16E4F-82D6-726C-8D76-8DE585D40107

Microsoft GUID (braces)

{01A16E4F-82D6-726C-8D76-8DE585D40107}

URN

urn:uuid:01a16e4f-82d6-726c-8d76-8de585d40107

32 hex digits

01a16e4f82d6726c8d768de585d40107

Base64 (RFC byte order)

AaFuT4LWcmyNdo3lhdQBBw==

128-bit integer (decimal)

2167425154582565186119808558224900359

.NET Guid.ToByteArray() (hex)

4f6ea101d6826c728d768de585d40107

.NET Guid bytes (Base64)

T26hAdaCbHKNdo3lhdQBBw==

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 01a16e4f-82d6-726c-8d76-8de585d40107 Copy

Formats

How to decode a UUID

Variant digit

Valid `01a16e4f-82d6-726c-8d76-8de585d40107`