Are these UUIDs generated privately?

Yes. Every UUID is generated locally in your browser using the cryptographically secure Web Crypto API. Nothing is sent to a server, logged, or stored — the values exist only on your device.

What is the difference between UUID v4 and UUID v7?

UUID v4 is fully random, which makes each value unpredictable but unordered. UUID v7 embeds a Unix millisecond timestamp in its most significant bits, so v7 values are time-ordered and sort chronologically — a big advantage as database primary keys and indexes.

Are these UUIDs guaranteed to be unique?

For all practical purposes, yes. A version 4 UUID has 122 random bits, giving roughly 5.3 x 10^36 possible values, so the chance of a collision is negligible. Version 7 adds a timestamp on top of random bits, making collisions even less likely.

Can I generate UUIDs in bulk?

Yes. You can generate between 1 and 1000 UUIDs at once, copy them all with a single click, or download the entire list as a .txt file.

What are the uppercase and no-hyphens options for?

Some systems expect UUIDs without hyphens (a plain 32-character hex string) or in uppercase. These formatting options let you match the exact format your database, API, or application requires.

UUID Generator

Generate random v4 and time-ordered v7 UUIDs instantly — privately in your browser.

Version

How many? (1–1000)

UppercaseNo hyphens

How it Works

Generate unique identifiers in three simple steps.

Pick a version

Choose UUID v4 for random identifiers or v7 for time-ordered ones.

Set count and format

Choose how many to generate and toggle uppercase or no-hyphen formatting.

Copy or download

Copy a single UUID, copy them all, or download the whole list as a .txt file.

UUID Tips

Choose and use UUIDs effectively with these tips.

Use v7 for database keys

Because v7 UUIDs are time-ordered, they keep database indexes compact and reduce page fragmentation compared to random v4 keys.

Use v4 for public tokens

When you don't want a value to reveal when it was created, v4's full randomness makes it a better fit than v7.

Match your target format

Some systems store UUIDs without hyphens or in uppercase. Use the format options so your IDs paste in cleanly.

Generate in bulk

Need seed data or test fixtures? Generate up to 1000 UUIDs at once and download them as a text file.