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UUID Generator

Bulk UUIDs, generated in your browser. Nothing is sent to a server.

Version

Random. 122 bits of entropy, no ordering — the safe default.

Generated locally with crypto.getRandomValues, the same source your browser uses for TLS keys — never Math.random().

About UUID Generator

Pick a version, pick how many, and copy the result. Generation happens entirely in your browser using the same cryptographic random source your browser uses for TLS — nothing is sent to a server, so the ids you paste into your code have never existed anywhere else. Output comes formatted for wherever it's going: a JSON array, a CSV column, or a ready-to-run SQL INSERT.

  • UUID v4 (random) and v7 (time-ordered, sorts by creation time)
  • Up to 10,000 at once, generated locally
  • Copy as plain text, JSON, CSV or SQL INSERT
  • Cryptographically secure randomness — never Math.random()

How to generate UUIDs

  1. 1Choose v4 for a plain random id, or v7 if it will be a database key.
  2. 2Set how many you need — up to 10,000.
  3. 3Pick an output format: plain, JSON, CSV or SQL.
  4. 4Copy to the clipboard, or download the file.

Frequently asked questions

What is the difference between UUID v4 and v7?
v4 is 122 bits of randomness, so two ids created a second apart have no relationship. v7 puts a millisecond timestamp in the first 48 bits, so ids sort in the order they were created. That makes v7 much better as a database primary key: rows go in at the end of the index instead of scattering writes across it.
Should I use UUID v7 for a primary key?
Usually yes, if your database supports storing it. Random v4 keys fragment the index because every insert lands in a random place; v7 keys are close to sequential, which keeps inserts and range scans fast. The trade is that a v7 leaks roughly when the row was created.
Are these UUIDs safe to use as tokens?
They are generated with crypto.getRandomValues, the browser's cryptographic random source — never Math.random(). A v4 has 122 random bits, which is plenty. Note that a v7 has 74 random bits and an embedded timestamp, so prefer v4 if the value must be unguessable.
Do the UUIDs get sent to your server?
No. Everything happens in your browser — the page makes no request while generating, and works offline once loaded. We never see the ids you produce.
Can I generate UUIDs in bulk?
Yes, up to 10,000 in one go, with output as a JSON array, a CSV column or a SQL INSERT statement so you can paste it straight into a seed file or migration.