Generate UUIDs (version 1, 4, 5 or 7) locally in your browser - cryptographically random and instant, with no upload.
Running locally on your device ...
No. Everything runs in your browser - your file never leaves your device. How this is verifiable
A UUID (Universally Unique Identifier, RFC 9562) is a 128-bit identifier that is practically guaranteed to be unique without any central authority handing it out. That is exactly what makes UUIDs the first choice for database keys, file and object names, correlation IDs in logs, or anywhere two independent systems must mint identifiers that never clash. This generator produces them instantly in the count you want.
You choose between version 1, version 4, version 5 and version 7. Version 1 is the classic timestamp type from the original standard: it combines a timestamp with a node identifier, which here is generated entirely at random for privacy - never from a real network address. Version 4 is almost entirely random and is the common default when order does not matter. Version 7 puts a timestamp at the front so the values sort chronologically - often faster as a primary key in modern databases, but it deliberately reveals the approximate creation time. Version 5 is different from the other three: it is name-based and deterministic - given a namespace (such as DNS or URL) and a name (such as a domain name), SHA-1 always computes the same UUID, handy for stable IDs derived from an existing identifier. The randomness for version 1, 4 and 7 comes from the browser cryptographically secure source (Web Crypto), not from a weak pseudo-random generator.
Generation runs entirely locally in your browser in pure JavaScript - nothing is uploaded, nothing is stored, and no foreign library is loaded from a CDN. Version 1, 4 and 7 need no input; version 5 needs a namespace (one of the four RFC standard namespaces, or a custom UUID) and a name. Optionally you can output the values in uppercase or remove the hyphens (32 plain hex characters). The result appears as a text file with one UUID per line that you can download.
Many online UUID generators show ads next to the result or cap the number of values generated at once in the free tier. This tool generates up to 1000 UUIDs per run with no ads, no account, and even works offline after the first load.
| Input formats | No file (generator) |
|---|---|
| Output format | TXT |
| Batch processing | No |
| Processing | Locally in your browser (JavaScript) |
| File upload | None |
Limitations: UUIDs are identifiers, not secrets: they are not suitable as a password or key - use the password generator for that. Version 4 is practically collision-free but not mathematically guaranteed unique. Version 1 and version 7 make the creation time roughly visible (version 1 additionally carries a random, never a real, node identifier); for version 7 that is how the ordering works. Version 5 is deterministic: the same namespace and name always yield the same UUID, so version 5 always produces exactly one value - the count option is ignored there. Otherwise at most 1000 values are produced per run (a deliberate cap for a reasonably sized output, not a mathematical or technical limit of UUID generation itself).
| Version | Source | Sortable? | Deterministic? | Privacy note |
|---|---|---|---|---|
| Version 1 | timestamp + node | roughly | no | node identifier here random (never real) |
| Version 4 | random | no | no | no special notes |
| Version 5 | namespace + name (SHA-1) | no | yes | name/namespace stay local |
| Version 7 | timestamp + random | yes | no | reveals the creation time |
No. The values are produced entirely locally in your browser and are not stored or sent - the namespace and name for version 5 never leave your device either.
Version 1 combines a timestamp with a node identifier - the classic type; here the node identifier is entirely random for privacy, never a real network address. Version 4 is almost pure randomness (no order). Version 5 is name-based and deterministic: namespace + name always produce the same UUID via SHA-1. Version 7 prepends a timestamp, so it sorts chronologically and is often a better database key, but it reveals the approximate creation time.
Practically yes. For version 4 the chance of a collision is so tiny that it is negligible in practice - only central assignment is truly guaranteed unique. Version 5 is intentionally reproducible: the same namespace and name give the same value every time, which is not a collision but the whole point.
For version 1, 4 and 7, the browser cryptographically secure source (Web Crypto), not a weak pseudo-random generator. Version 5 uses no randomness at all - it is deliberately deterministic.
A fixed UUID that defines the kind of name (DNS for domain names, URL, OID or X.500). The four standard namespaces come from RFC 9562/4122; alternatively you can enter your own UUID as the namespace.
Better not. A UUID is an identifier with a fixed structure, not a secret. For passwords use the password generator with adjustable length and character set.
Yes, in any current mobile browser just like on desktop - the UUIDs are produced locally on the device.
No, it is completely free, with no account. Up to 1000 values are possible per run; for more, just generate again.
Yes. After the page first loads, generation even works in airplane mode, because it runs entirely in the browser.
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