Need a UUID? The ChrysoKit UUID Generator produces cryptographically random v4 UUIDs, one at a time or in bulk, with the format options developers actually use.
Why use it
Web Crypto randomness, no telemetry, instant copy. The generator runs locally; the UUIDs it gives you were never anywhere else.
How to use the UUID Generator
- Click Generate one for a single UUID, or set a bulk count (up to 1000).
- Pick a format: lowercase, UPPERCASE, no hyphens, or wrapped in braces.
- Copy a single value with the copy icon, copy all, or download the bulk list as a .txt file.
Features worth knowing
v4 only, cryptographically random
Every UUID is 128 bits, of which 122 are random and 6 are reserved for the version and variant marker. v4 is the right default for distributed IDs and the most common choice. v1 and v7 (time-based UUIDs) are on the roadmap.
Bulk mode
Generate up to 1000 UUIDs in one go for seeding test data, populating a fixture file, or stress-testing an import script.
Four format options
lowercase, UPPERCASE, no-hyphens, and braces (Microsoft Registry style). Pick the one your target system expects.
Pro tips
- v4 is the right default unless you have a specific reason to pick another version. The randomness is plenty for distributed primary keys.
- If you need time-sortable IDs (better index locality), look up v7. Once it ships in the tool you can swap straight in.
- Download bulk lists as .txt to seed a test database or feed into a fixture script.
Privacy first. The UUID Generator runs entirely in your browser. Nothing you generate is sent to a server.
Pair the UUID Generator with bulk mode when you are seeding a database; reach for one-at-a-time when you just need a fresh ID. Copy and move on.
Open the tool: UUID Generator →
Choosing IDs for a new project: a decision walkthrough
A developer starting a side project faces the identifier question in the first hour: auto-increment integers, or UUIDs? The walkthrough that settles it is worth recording. Sequential integers are compact, index-friendly and human-readable... and they leak business intelligence by existing. Order number 1047 tells a competitor you have processed about a thousand orders; checking order 1048 from another account is the classic insecure-direct-object-reference probe. UUIDs end both problems at the cost of 36 characters and index locality.
The project in question chose a hybrid that has become something of an industry default: internal integer primary keys for join performance, plus a UUID exposed in every URL and API response. The database stays fast; the outside world sees only opaque identifiers that enumerate nothing.
One incident from later in the same project illustrates the generator's other everyday job: a CSV import needed stable IDs for 3,000 legacy records before the database ever saw them. Minting UUIDs in bulk, offline, with zero coordination... no sequence to reserve, no collision meeting with the other team... took seconds, and the records kept those identities through three subsequent system migrations. That coordination-free property, more than randomness itself, is what UUIDs actually sell.