UUID Generator
Generate random UUIDs (v4), time-ordered v7, time-based v1 and name-based v5 — one at a time or up to 1,000 in bulk.
Generate UUID
Bulk Generate
Validate / inspect a UUID
About UUID v4
UUID v4 is built entirely from random bits. It carries no timestamp or machine information, which makes it the most widely used version and the safest default when you simply need an identifier that will never collide.
xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
- 4 - the version nibble, always 4
- y - the variant: 8, 9, a or b (binary 10xx)
- x - a random hex digit; 122 random bits in total
Statistics
Fun Facts
- There are 2122 possible v4 UUIDs (about 5.3 × 1036) - a collision is practically impossible
- v7 UUIDs sort by creation time, which keeps database indexes compact and inserts fast
- v5 UUIDs are deterministic: the same namespace and name give the same UUID every time, on every platform
- No central authority is needed - any machine can mint ids offline
- GUID is Microsoft's name for the same 128-bit format
This UUID generator creates universally unique identifiers in your browser — a random UUID v4 by default, plus UUID v7 (time-ordered and sortable), v1 (time-based) and v5 (deterministic, from a namespace and a name). Generate a single UUID or up to 1,000 at once, format them with or without hyphens, in braces or as a URN, in lower or upper case, then copy or download the list. A UUID is a 128-bit value written as 32 hexadecimal digits in the 8-4-4-4-12 pattern, for example f47ac10b-58cc-4372-a567-0e02b2c3d479.
Which UUID version should I use?
| Version | Built from | Best for |
|---|---|---|
| v4 (random) | 122 random bits | The default: request IDs, API keys, idempotency keys, any identifier that must be unpredictable |
| v7 (time-ordered) | Unix-millisecond timestamp + random bits | Database primary keys — sorts by creation time, so indexes stay compact |
| v1 (time-based) | 100-nanosecond timestamp + clock sequence + node id | Systems that expect v1; this tool uses a random node id, not your MAC address |
| v5 (name-based) | SHA-1 of a namespace UUID + a name | Stable identifiers derived from a name (a domain, a URL): the same input always gives the same UUID |
All randomness comes from the browser's cryptographic generator (crypto.getRandomValues), and nothing is sent to a server. The inspector at the bottom of the tool decodes any UUID you paste: its version, variant and, for v1 and v7, the embedded timestamp.
UUID vs GUID
A GUID is the same thing under Microsoft's name. Windows and .NET usually show GUIDs in uppercase and braces — {F47AC10B-58CC-4372-A567-0E02B2C3D479} — which you can produce here by choosing "With braces" and "UPPERCASE", or with the dedicated GUID generator. The history and trade-offs are covered in UUID and GUID explained.
Gerador de UUID · UUID generieren · Générateur d'UUID
Português: Este gerador de UUID cria identificadores únicos (v4 aleatório, v7 ordenado por tempo, v1 e v5) diretamente no seu navegador. Gere um UUID ou até 1.000 de uma vez e copie com um clique.
Deutsch: Mit diesem Tool können Sie UUIDs generieren (v4, v7, v1 und v5) — einzeln oder bis zu 1.000 auf einmal, direkt im Browser und ohne Anmeldung.
Français : Ce générateur d'UUID crée des identifiants uniques (v4, v7, v1 et v5) dans votre navigateur, un par un ou jusqu'à 1 000 à la fois.