Tools Generators
UUID Generator
Generate random v4 or time-ordered v7 UUIDs, one or up to 100,000 as a file.
🔒 Runs in your browser. Nothing is uploaded.How to use it
- Choose v4 (fully random) or v7 (time-ordered).
- Pick how many to generate, from 1 to 100,000.
- Click Generate, then copy one line, copy all of them, or download them as a .txt file.
- For more than 1,000, the UUIDs go straight into a .txt file, one per line, instead of being shown on the page.
Questions
Should I use v4 or v7?
Use v7 for database primary keys: its leading timestamp keeps new rows close together in an index, which is faster to insert. Use v4 when an ID must not reveal when it was created.
Are these UUIDs secure?
They come from the browser’s cryptographically secure random number generator (crypto.getRandomValues). v7 also contains the creation time to the millisecond, so treat that part as public.
Why are large batches downloaded instead of shown?
Showing tens of thousands of rows would freeze the page. Above 1,000, the UUIDs are written straight to a text file in your browser, so even 100,000 take about a second.
Can two generated UUIDs collide?
In practice, no. A v4 UUID has 122 random bits; you would need to generate billions per second for decades to expect a single collision.