UUID Generator
Generate UUIDs in bulk — classic random v4 or time-ordered v7 — with your browser’s cryptographic random generator. Toggle hyphens, casing and braces, and copy them all with one click. Nothing is sent to a server.
- 🔒 100% private — no uploads
- 🆓 Free, no watermark
- 📱 Works on any device
How to generate a UUID
- 1
Pick a version
Choose v4 (fully random) or v7 (time-ordered). Set how many you want with the slider.
- 2
Generate instantly
IDs are created with your browser’s cryptographic random generator — nothing is requested from a server.
- 3
Format & copy
Toggle hyphens, uppercase or braces, then copy them all with one click. Regenerate for a fresh batch anytime.
Why use UUID Generator?
v4 and v7
Classic random v4 UUIDs, or time-ordered v7 (RFC 9562) that sort by creation time — ideal as database keys.
Bulk & formatted
Generate up to 50 at once and toggle hyphens, casing and braces to match whatever your code or database expects.
100% private
Everything runs locally in your browser with JavaScript. Your input is never uploaded, stored or seen by anyone — it even works offline once the page has loaded.
Works on any device
No install and no account. Runs in any modern browser on Windows, macOS, Linux, Android or iPhone.
How unlikely is a collision, really?
A v4 UUID contains 122 random bits, giving about 5.3 × 10³⁶ possible values. By the birthday math, you’d need to generate roughly a billion UUIDs per second for around 85 years before the odds of a single collision reach 50%. In practice: generate freely, don’t check for duplicates, and treat any “duplicate UUID” bug as a copy-paste or caching problem — because statistically, it is.
Picking v4 or v7 for database keys
Random v4 keys scatter inserts all over a B-tree index, which hurts locality and cache behaviour on write-heavy tables. v7 puts a millisecond timestamp in the high bits, so new rows land near each other and records sort naturally by creation time — the same idea that made ULIDs popular, now standardized in RFC 9562. Use v7 for primary keys, and v4 where you specifically don’t want IDs to reveal creation order.
Frequently asked questions
Are these UUIDs unique and safe to use?
Yes. v4 UUIDs use 122 random bits from your browser’s cryptographic generator, so collisions are astronomically unlikely. v7 keeps that randomness but prefixes a timestamp so the IDs sort in creation order.
What’s the difference between v4 and v7?
v4 is fully random. v7 (RFC 9562) puts a millisecond timestamp at the front and fills the rest with randomness, so the IDs are still unique but sort in creation order — handy as database primary keys.
Is a GUID the same as a UUID?
Yes. GUID (globally unique identifier) is Microsoft’s term for the same 128-bit value the rest of the world calls a UUID. They’re interchangeable — use the braces and uppercase toggles for the .NET and SQL Server style.
Is my data uploaded to a server?
No. The tool runs entirely in your browser, so whatever you paste stays on your device. It’s safe for tokens, secrets and confidential data, and works offline once loaded.