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UUID Generator

Create one or thousands of universally unique identifiers in any version, formatted exactly the way your code or database expects.

Processed locally in your browser

Options

Only used by v3 / v5.

Used when the namespace is “Custom”.

Only used by v3 and v5. With more than one UUID, -1, -2… is appended to the name.

What is UUID Generator?

A UUID (universally unique identifier) is a 128-bit value, usually written as 32 hexadecimal digits in the 8-4-4-4-12 pattern. Version 4 is purely random, version 7 starts with a millisecond timestamp so values sort by creation time, versions 1 and 6 embed a clock reading, and versions 3 and 5 derive the value from a namespace and a name.

This generator uses the browser’s cryptographic random source. You choose the version, the quantity (1 to 1,000), letter case, hyphens, wrappers such as {braces} or quotes, the separator, and whether you want plain text, CSV with a header or a JSON array.

How does it work?

  1. Pick the UUID version (v4 is the default for random IDs, v7 for database keys that should sort by time).
  2. Choose how many you need and the formatting: uppercase, hyphens, wrappers and separator.
  3. For v3 or v5, also set the namespace and the name; the same pair always yields the same UUID.
  4. Click Generate, then copy the list or download it as uuids.txt, CSV or JSON.

Common use cases

  • Seeding a test database with hundreds of unique primary keys.
  • Creating request or correlation IDs for logs and tracing.
  • Producing GUIDs in braces for .NET, Windows registry or COM code.
  • Building deterministic identifiers for records that must map to the same ID every time.

Examples

Create one or thousands of universally unique identifiers in any version, formatted exactly the way your code or database expects.

Privacy

UUID Generator runs entirely in your browser. The text or files you provide are processed on your device and are not uploaded, logged or stored on our servers.

Limitations

UUIDs are identifiers, not secrets: never use one as a password or an access token. Version 1 normally exposes a MAC address, so this tool uses a random node ID instead.

Frequently asked questions

Which UUID version should I choose?

Use v4 for general random IDs and v7 when the IDs will be database keys, because v7 values are roughly ordered by creation time and keep indexes efficient. Use v5 when the same input must always give the same ID.

Can two generated UUIDs collide?

A v4 UUID has 122 random bits, so an accidental collision is astronomically unlikely, even across billions of values. Name-based versions collide only when you feed them the same namespace and name, which is intended.

Are the UUIDs generated on a server?

No. Everything is produced in your browser with crypto.getRandomValues, and nothing is uploaded or stored.

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