UUID v4 and v7 Generator
Generate one or many UUIDs as version 4 (random) or version 7 (time-sortable), with options for uppercase, bare hex without hyphens and brace wrapping. Randomness comes from the browser cryptographic generator, and the millisecond timestamp at the front of a v7 keeps database primary keys inserting in order.
How to use
Generate UUID v4 or time-sortable v7 in batches, entirely offline. Your data is processed only inside this browser tab.
FAQ
When is v7 better than v4?
As a database primary key. The first 48 bits are a Unix millisecond timestamp, so inserts stay roughly ordered and index pages stop fragmenting.
Are these really random?
The random part comes from crypto.getRandomValues on your device — 122 bits for a v4 and 74 bits for a v7.
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