UUID Generator — Random v4 and Time-Ordered v7 UUIDs in Bulk

How to use the UUID generator

1. Choose the Version: v4 (random) or v7 (time-ordered).
2. Set How many UUIDs, from 1 to 1,000.
3. Tick Uppercase, Wrap in braces, or untick Hyphens, to match the format your system expects.
4. Press Generate and copy one UUID or the whole list.

What it does and when to use it

A UUID (universally unique identifier) is a 128-bit ID that any computer can create on its own, with no central counter, and still not clash with IDs made elsewhere. That makes UUIDs useful wherever separate systems, devices or services each need to make up their own keys.

Typical uses:

• Primary keys for database rows, especially across several servers.
• IDs for records created offline in a mobile app and synced later.
• Request or correlation IDs in logs and distributed tracing.
• File names that must never collide.
• Test data and fixtures.

For shorter IDs, try the CUID Generator. For secrets, which must be unpredictable as well as unique, use the Strong Password Generator or the API Key Generator instead.

How it works

Both versions follow RFC 9562, the current UUID standard.

• Version 4 fills 122 bits with random data from crypto.getRandomValues, the browser’s secure random source. The remaining 6 bits mark the version and variant. You can spot a v4 UUID by the 4 at the start of the third group, as in xxxxxxxx-xxxx-4xxx-….
• Version 7 starts with a 48-bit timestamp in milliseconds, followed by 74 random bits. UUIDs made later sort after earlier ones. Within one batch, the tool makes sure every UUID is strictly larger than the one before, even when several are made in the same millisecond.

The format options only change how the 128 bits are written: lowercase or uppercase hex, with or without hyphens, with or without braces. Everything runs in your browser and nothing is stored.

Worked examples

Two random v4 UUIDs. With the defaults, the tool produces values like ab2c463e-73ff-43b7-8276-7e6feccaf8c6. Note the 4 at the start of the third group. The note under the list confirms Version 4: 122 random bits from crypto.getRandomValues (RFC 9562). Your values will be different every time, which is the point.

Two v7 UUIDs, uppercase in braces. The output looks like {01A1003F-5014-7688-A05E-196D4D24944C} followed by {01A1003F-5014-7688-A05E-196D4D25772F}. Both share the same timestamp prefix, the third group starts with 7, and the second sorts after the first. The note confirms This batch is in strictly increasing order.

Limits and tips

• A v7 UUID shows roughly when it was made. Use v4 if that matters.
• UUIDs are unique, not secret. Do not use them as passwords, tokens or keys.
• Some systems want uppercase or braces, and others reject them. Check before you paste.