UUID & MAC Utils by Daniel Marschall

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Overview

Generate random and/or time-based UUIDs

New: Generate Unix Epoch time-based (version 7) UUID ⭐

A UUIDv7 measures time in the Unix Epoch with an accuracy between 1ms and 245ns, depending on how many bits are spent for the timestamp (48-60 bits). The rest of the UUID (62-74 bits) is filled with random data. The timestamp is at the front of the UUID, therefore the UUIDs are monotonically increasing, which is good for using them in database indexes. Since this UUID version does not contain a MAC address, it is also recommended due to the improved privacy.

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Here are 15 UUIDs that were created just for you! (Reload the page to get more)

0190b5b6-dc75-7f13-bdbc-a4febb2fc1e7
0190b5b6-dc76-70ad-b6e8-2f33ee42991c
0190b5b6-dc76-71ec-8315-dd594df1ce5d
0190b5b6-dc76-730f-bd76-563d43187337
0190b5b6-dc76-742e-8f51-db2bc3fd8253
0190b5b6-dc76-754c-a955-67ed720bd85f
0190b5b6-dc76-7667-b7ac-de5014a2e647
0190b5b6-dc76-7786-a7a2-43c42bfbb2f4
0190b5b6-dc76-78a0-aabe-9d83184040c1
0190b5b6-dc76-79bb-a3ea-2753ba5c61ee
0190b5b6-dc76-7ad1-8dbe-82b8a3f39e58
0190b5b6-dc76-7bec-9b28-d114de05d44d
0190b5b6-dc76-7d03-8382-4f06a8ce3f92
0190b5b6-dc76-7e21-807a-5fbd11b899a1
0190b5b6-dc76-7f3c-acc4-89b3091bfa10

New: Generate reordered Gregorian time-based (version 6) UUID ⏰

Like UUIDv1, this kind of UUID is made of the MAC address of the generating computer, the time, and a clock sequence. However, the components in UUIDv6 are reordered (time is at the beginning), so that UUIDs are monotonically increasing, which is good for using them in database indexes.

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Here are 15 UUIDs that were created just for you! (Reload the page to get more)

1ef428c4-a852-6a8c-8a8e-4cf95d479851
1ef428c4-a852-6c30-8a8e-4cf95d479851
1ef428c4-a852-6d16-8a8e-4cf95d479851
1ef428c4-a852-6dde-8a8e-4cf95d479851
1ef428c4-a852-6ea6-8a8e-4cf95d479851
1ef428c4-a852-6f6e-8a8e-4cf95d479851
1ef428c4-a853-6036-8a8e-4cf95d479851
1ef428c4-a853-60fe-8a8e-4cf95d479851
1ef428c4-a853-61bc-8a8e-4cf95d479851
1ef428c4-a853-627a-8a8e-4cf95d479851
1ef428c4-a853-63ba-8a8e-4cf95d479851
1ef428c4-a853-648c-8a8e-4cf95d479851
1ef428c4-a853-654a-8a8e-4cf95d479851
1ef428c4-a853-6608-8a8e-4cf95d479851
1ef428c4-a853-66c6-8a8e-4cf95d479851

Generate random (version 4) UUID 🎲

A UUIDv4 is made of 122 random bits. No other information is encoded in this kind of UUID.

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Here are 15 UUIDs that were created just for you! (Reload the page to get more)

d65b5067-b90e-4931-9fcc-93aade99e136
8f09cf9c-4e26-4360-9914-9d0eb8a93852
91612745-5904-446b-a6c9-f06b9e4f73e8
7f4fb705-854a-4421-9bef-53ebe4707570
a7f7a34d-9caf-41b4-acce-1b7ddb342f31
19c81d99-fb3b-4500-854d-7d40dd1249d1
4de8ac07-058c-43a7-be67-c4eb8da42ce2
679dfe41-f239-4e13-8e3b-b51ecd1de192
98debb06-9fc8-4f58-aed6-a4b64cb4c6e7
9d7b515c-209e-4bb0-af24-c808272381fa
2235a122-a5ca-4f23-9437-68ef36056200
dacecab6-c56e-467b-ba10-f00eb8d077ea
da6bb703-e4b4-4f9a-8c30-ec86f134f153
3e67b1c9-3ea0-484b-8c6e-c92bdfb2dd53
2e79e96d-74b8-4f93-975a-5607e5750418

Generate Gregorian time-based (version 1) UUID ⏰

A UUIDv1 is made of the MAC address of the generating computer, the time, and a clock sequence.

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Here are 15 UUIDs that were created just for you! (Reload the page to get more)

4a853bee-428c-11ef-8a8e-4cf95d479851
4a853c52-428c-11ef-8a8e-4cf95d479851
4a853cb6-428c-11ef-8a8e-4cf95d479851
4a853d10-428c-11ef-8a8e-4cf95d479851
4a853d74-428c-11ef-8a8e-4cf95d479851
4a853dce-428c-11ef-8a8e-4cf95d479851
4a853e32-428c-11ef-8a8e-4cf95d479851
4a853e8c-428c-11ef-8a8e-4cf95d479851
4a853ef0-428c-11ef-8a8e-4cf95d479851
4a853f54-428c-11ef-8a8e-4cf95d479851
4a853fb8-428c-11ef-8a8e-4cf95d479851
4a854026-428c-11ef-8a8e-4cf95d479851
4a85408a-428c-11ef-8a8e-4cf95d479851
4a8540ee-428c-11ef-8a8e-4cf95d479851
4a854152-428c-11ef-8a8e-4cf95d479851

Generate SQL Server sortable time-based (version 8) UUID

The sorting of UUIDs in SQL Server is rather confusing and incompatible with UUIDv6 and UUIDv7.
Therefore this method developed by HickelSOFT generates UUIDs which are sortable by SQL Server.
They have a time resolution of 1 milliseconds combined with 16 bits of random data.

C# implementation | PHP implementation

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Here are 15 UUIDs that were created just for you! (Reload the page to get more)

ed2d7c12-0237-80c5-87e8-5ce32bd83b96
08da7d12-0237-80c5-87e8-5ce32bd83b96
63227e12-0237-80c5-87e8-5ce32bd83b96
ce9e7f12-0237-80c5-87e8-5ce32bd83b96
c3878112-0237-80c5-87e8-5ce32bd83b96
49e88212-0237-80c5-87e8-5ce32bd83b96
2fce8312-0237-80c5-87e8-5ce32bd83b96
41668412-0237-80c5-87e8-5ce32bd83b96
c4468512-0237-80c5-87e8-5ce32bd83b96
01408612-0237-80c5-87e8-5ce32bd83b96
bcfa8712-0237-80c5-87e8-5ce32bd83b96
d2a18812-0237-80c5-87e8-5ce32bd83b96
b86e8912-0237-80c5-87e8-5ce32bd83b96
91d98a12-0237-80c5-87e8-5ce32bd83b96
bcf78b12-0237-80c5-87e8-5ce32bd83b96

Generate other UUID types

The following types of UUIDs are less common and/or require special knowledge. Please only use the following generators if you know what you are doing.

NCS (variant 0) UUID

The NCS UUIDs are a legacy format initially designed by Apollo Computer that cannot be generated anymore, because the amount of available timestamp bits was exhausted on 5 September 2015. As an example, here is the last possible NCS UUID (all bits of the timestamp are set to 1) for IP address 127.0.0.1: ffffffff-ffff-0000-027f-000001000000.

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Generate DCE Security (version 2) UUID

An UUIDv2 contains information about the creator (person, group, or organization), the generating system (MAC address), and time. The creator information replaced parts of the time bits, therefore the time resolution is very low.

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= Address Family ID: (decimal notation)
(decimal notation)
Warning: The timestamp has an accuracy of 7:10 minutes, therefore the uniqueness of these UUIDs is not guaranteed!

Generate name-based (version 3 / 5 / New: 8) UUID

An UUIDv3 is made out of a MD5 hash and an UUIDv5 is made out of a SHA1 hash. RFC 9562 also contains an example for a custom UUIDv8 implementation that uses modern hash algorithms.

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= Namespace UUID:

Warning: These UUIDs do not contain a timestamp, therefore the uniqueness of these UUIDs is not guaranteed!

New: Generate Custom (version 8) UUID

UUIDv8 is made of 122 bits application-specific / custom data. The other 6 bits are used to specify the variant and version of the UUID, to make it RFC-compatible.

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0x = Decimal
0x = Decimal
0x = Decimal
0x = Decimal
0x = Decimal
Warning: These UUIDs do not contain a timestamp, therefore the uniqueness of these UUIDs is not guaranteed!

Interpret a UUID

You can enter a UUID in the following notations:

The script will output:

Please enter a UUID or UUID OID:

Interpret a MAC address (MAC / EUI / ELI / SAI / AAI)

You can enter a UUID in the following notations:

The script will output:

Please enter a MAC (EUI, ELI, SAI, AAI), or IPv6-Link-Local address:

Generate an AAI

An Administratively Assigned Identifier (AAI) is a MAC address which can be locally defined by applications or an administrator. Unlike the EUI, an AAI is NOT worldwide unique.


The following options are rather unusual, but are implemented for the sake of completeness: