Generate version 4 UUIDs using the browser's cryptographic random number generator, one at a time or in batches, with formatting options for uppercase, hyphen-free and braced variants.
Getting started
Choose how many identifiers you need, from one to several hundred.
Select a format — standard hyphenated, uppercase, without hyphens, or brace-wrapped.
Press generate to produce a fresh batch.
Copy the whole list or download it as a text file.
Why it helps
Uses crypto.getRandomValues rather than Math.random, so identifiers are genuinely unpredictable.
Bulk generation saves running a script when seeding a database or test fixture.
Format options match the conventions of different languages and databases.
Generated locally, so identifiers are never seen by anyone else before you use them.
In practice
Seeding a database with primary keys during development.
Creating correlation identifiers for tracing a request across microservices.
Generating idempotency keys for API requests that must not be duplicated.
Producing unique file or object names that cannot collide.
Everything people ask most about the uuid generator, answered plainly.
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