Create strong random passwords or passphrases using your browser’s secure random generator.
UUID Generator
Generate random v4 or time-ordered v7 UUIDs in bulk, in the format you need.
Generated on your device with Web Crypto — never sent anywhere
How it works
- v4: 16 random bytes from
crypto.getRandomValues; the version nibble is set to 4 and the variant bits to 10 (RFC 9562). - v7: the first 48 bits are the current Unix time in milliseconds, then the version (7), then random bits. Several v7 UUIDs generated in the same millisecond still sort correctly because the random part is incremented.
Format options only change how the 128-bit value is written, not the value itself.
Example
A v4 UUID looks like 3f2b8c1e-9a4d-4e7b-b1c2-5d6e7f8a9b0c — note the 4 at the start of the third group. A v7 UUID such as 019a1b2c-3d4e-7f50-8a1b-2c3d4e5f6a7b has a 7 there, and its first 12 hex digits encode the time it was created.
Frequently asked questions
What is the difference between UUID v4 and v7?
Version 4 UUIDs are entirely random (122 random bits). Version 7 UUIDs (RFC 9562) start with a Unix timestamp in milliseconds followed by random bits, so they sort in creation order — useful as database keys because inserts stay in index order.
Are these UUIDs unique?
They are generated with your browser’s cryptographically secure random number generator. The chance of two random v4 UUIDs colliding is so small it can be ignored for practical purposes.
Is a GUID the same as a UUID?
Yes — GUID is Microsoft’s name for the same 128-bit identifier format. Some systems display GUIDs in uppercase or wrapped in braces; use the format options to match.
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