Generate version 4 and version 7 UUIDs in bulk, using secure randomness.
00000000-0000-0000-0000-000000000000
Single v4
One random identifier — the common case
1Batch of 25
Seed a test fixture or a migration
25Large batch
Generate in bulk and download
500Version 4 for general use. Version 7 when identifiers will be database keys and you want them to sort by creation time.
Generate a single value or up to a thousand at once, with or without hyphens and in upper or lower case.
Copy the list to the clipboard, or download it as a text file when the batch is large.
Values come from the browser’s secure random generator, so they are not predictable — which matters whenever an identifier is also a capability.
Time-ordered identifiers keep index inserts sequential, avoiding the write amplification that random v4 keys cause at scale.
Producing hundreds at once is far quicker than clicking generate repeatedly when seeding test data.
Generate universally unique identifiers one at a time or a thousand at once. Version 4 is pure randomness and the right default for most purposes. Version 7 puts a millisecond timestamp at the front, so identifiers sort chronologically — a meaningful advantage as a database primary key, because randomly ordered keys fragment B-tree indexes badly. Every value uses your browser’s cryptographic random number generator, never a predictable pseudo-random source.
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