UUID generator
Generate bulk UUID v4 identifiers with cryptographic randomness. Copy the list or download it as text.
About this tool
UUIDs are the identifiers developers reach for when records, files or sessions need unique IDs without a central counter. This generator produces version 4 UUIDs as specified by RFC 9562 — 122 bits of cryptographic randomness drawn from crypto.getRandomValues — in batches of up to 1,000 at a time.
Formatting options cover the systems that are picky about presentation: uppercase output, or a compact form without hyphens; the underlying identifier is the same either way. Copy the list or download it as a text file. At 122 random bits, collisions are not a practical concern — you would need to generate billions per second for a century to reach even odds of a single one.
How to use UUID generator
- Choose how many UUIDs to generate (1–1000) and formatting options.
- Generate the list.
- Copy it or download as a .txt file.
Keep the original files and inspect the exported result before publishing or sharing it.
Frequently asked questions
What is a UUID v4?
A 128-bit identifier with the version nibble set to 4 and the variant bits set per RFC 9562. The remaining 122 bits are random.
Can two UUIDs collide?
Effectively never. With 122 random bits, you would need to generate billions per second for a century to reach even odds of one collision.
Where does the randomness come from?
crypto.getRandomValues, the browser’s cryptographically secure random number generator.
What do the uppercase / no-hyphens options do?
They only change display formatting, for systems that expect compact or uppercase IDs. The underlying identifier is identical.
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