Generate UUIDs (v4)
Cryptographically random v4 UUIDs, one or many.
Files stay on your device. No accounts. Free.
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About this tool
Generates version 4 UUIDs using your browser's cryptographic random number generator, the same crypto.randomUUID API you would call in code. Make one, or a whole column of them for seeding a database or spreadsheet.
UUIDs are generated on your device the moment you click, they are not drawn from any shared pool or logged anywhere, so they are yours alone.
How it works
- Paste your input, or drop a text file onto the box.
- The output updates live as you type.
- Copy it to the clipboard, or download it as a file.
Frequently asked questions
What is a version 4 UUID?
A 128-bit identifier where 122 bits are random, formatted as five hyphen-separated groups like 8b4f...-....-4...-....-... . The 4 marks the version. With that much randomness, collisions are not a practical concern.
Are these UUIDs unique and safe to use in production?
Yes. They come from crypto.randomUUID, which uses the operating system's cryptographic randomness, exactly what server frameworks use. Generating them here or in your code produces the same class of identifier.
Can I generate many UUIDs at once?
Yes, set the count and generate up to a thousand in one click, one per line, ready to copy into a script, database seed or spreadsheet column.