UUID Generator (v4, v7)

How to use

This tool creates UUIDs (also called GUIDs), the 128-bit identifiers used for database keys, file names and API requests.

1. Pick a Version. Version 4 is fully random and is the safe default. Version 7 starts with the current time, so new IDs sort after older ones. That makes v7 a good choice for database primary keys, where ordered inserts are faster.
2. Enter How many you need, from 1 to 10,000, and press Generate. A fresh UUID is ready as soon as the page loads.
3. Choose a format. Uppercase switches the letters to capitals. Braces wraps each UUID in curly brackets, the way some Windows tools expect. No hyphens gives you 32 plain hex digits.
4. Press Copy to put them on your clipboard, one per line, or Download .txt to save a file.

v5 (from a name) makes the same UUID every time for the same name, so two systems can agree on an ID without sharing a list. Pick a Namespace, such as DNS for domain names or your own UUID, and type names, one a line. Names are used exactly as typed, spaces and capitals included.

To check an existing UUID, paste it into Check a UUID. You see whether it is valid and which version it is. For version 7 you also see when it was created.

Randomness comes from your browser's cryptographic random number generator. Version 7 UUIDs made here are always in increasing order, even thousands in the same millisecond.

Your chosen version, count and format are remembered on this device. The UUIDs themselves are not stored or sent anywhere.

Frequently asked questions

Should I use UUID v4 or v7?

Use v4 when you just need a unique ID and the order does not matter. Use v7 for database keys and logs, because v7 IDs sort by creation time, which keeps indexes compact and inserts fast.

Can two generated UUIDs ever be the same?

In practice, no. A v4 UUID has 122 random bits. You would need to generate billions of them every second for many years before a duplicate became likely.

Is a GUID the same as a UUID?

Yes. GUID is the name Microsoft uses for the same 128-bit format. Turn on uppercase and braces to get the {XXXXXXXX-...} style that Windows tools often show.