JPKCom DB

UUID Generator

Generate UUIDs v4, v7, v6, v1, v5 and v3 (RFC 9562) in your browser, up to 10,000 at a time, decode any UUID and output it in seven formats.

Generate unique identifiers — six versions and a decoder

The UUID Generator creates Universally Unique Identifiers (UUIDs, the same thing as GUIDs) right inside your browser. You pick a version from the tabs, set a count if you need more than one, and click the tab's Generate button — out come one or many fresh identifiers, ready to copy or to download as a text file. It also works the other way round: the Decode tab takes any existing UUID apart and shows you what is inside.

UUIDs are 128-bit values that are practically collision-free without any central authority handing them out: ideal as database primary keys, as correlation IDs for log entries and distributed systems, as file names, or as stable keys in APIs. The tool is aimed at developers, DevOps and database people, and anyone who needs a valid, standards-compliant identifier quickly, without writing a script or pulling in a library.

What the UUID Generator does — at a glance

  • Six UUID versions across four generator tabs: v4 Random, v7 Time-ordered (sortable and monotonic), v6 / v1 Time-based (Gregorian timestamp), and v5 / v3 Name-based (derived from a name via SHA-1 or MD5).
  • Bulk generation for v4, v7, and v6/v1: 1 to 10,000 UUIDs in one run, one per line. Even in a batch, v7 and v6 stay in strict creation order.
  • Name-based for whole lists: with v5/v3, every line in the names field yields one UUID; each name counts exactly as typed, and the tool flags leading or trailing spaces.
  • Namespace choice for v5/v3: the predefined namespaces (DNS, URL, OID, X.500) or your own namespace as a UUID.
  • Decoder: read version, variant, timestamp (UTC and local), clock sequence, and node from up to 200 lines at once — with braces, as a URN, without hyphens, or in Base64.
  • Seven output formats: standard, upper case, without hyphens, {Braces}, urn:uuid:, Base64, and Base64url — switchable without regenerating.
  • NIL and Max UUID (00000000-… and ffffffff-…) always at hand in the card footer, each with its own copy button.
  • Copy or download — send the result to the clipboard or save it as uuids.txt.

Which version for what?

Each version solves a different problem — and the tabs spell out the recommendation:

  • v4 Random is the usual choice when the ID does not need to sort: 122 random bits, no time or device information.
  • v7 Time-ordered starts with a Unix timestamp in milliseconds and is monotonic: even UUIDs from the same millisecond sort in creation order — which makes them good database primary keys.
  • v6 / v1 Time-based use a Gregorian timestamp (in 100 ns units), a clock sequence, and a random node, so no MAC address is revealed. v6 sorts by time; you only need v1 when a system insists on it.
  • v5 / v3 Name-based are deterministic: the same namespace and the same name always produce the same UUID — good for deriving stable identifiers from existing names (domains, URLs). v5 uses SHA-1; v3 (MD5) is only there for compatibility with older systems.

Which version carries which bits, and exactly how the tool builds them, is covered in the manual.

Architecture: runs entirely in the browser

Generating and decoding happen 100% client-side — there is no server call, no transmission, no account. The random values for v4, v7, and v6/v1 come from the browser's cryptographically secure random generator (crypto.getRandomValues or crypto.randomUUID), not from Math.random. v5 computes its identifier with a SHA-1 hash from the Web Crypto API, which requires a secure context (HTTPS); for v3 the tool ships its own MD5 implementation, because Web Crypto has no MD5. The only thing stored is your chosen output format, in your browser's localStorage — generated UUIDs and names are not.

Try it now

→ Open the UUID Generator — pick a tab, click Generate, then copy or download. No account, free, right in the browser.

  • Hash generator — compute checksums and hashes (MD5, SHA-1, SHA-256, and more); related to the SHA-1 and MD5 derivation behind v5 and v3.
  • Time Converter — convert timestamps and compare time zones, for example the time the decoder reads out of a v7, v6, or v1 UUID.
  • Password & key generator — produce random tokens, passwords, and keys when you need freely chosen strings rather than a standards-compliant 128-bit identifier.
  • Cryptor (AES-256) — encrypt text client-side; also built on the browser's Web Crypto API.

There's more on the sub-pages: the manual with every version, option, and the decoder, real-world examples, and collected tips & tricks.