Generate version-4 UUIDs using the browser's cryptographically secure random source (crypto.randomUUID). Make a single identifier or a batch of up to 25 at once, then copy them individually or all together. Everything is generated locally — no server, no upload, no rate limit. Perfect for seeding test data, database keys, and correlation IDs. Free, no signup, no ads on the tool.
A UUID is a 128-bit identifier designed so that independent systems can each mint IDs without coordinating and still not collide. Version 4 — the kind generated here — fills 122 of those bits with randomness, which is enough that the practical chance of two colliding is negligible even across billions of values. That property is what makes UUIDs useful for database keys, request tracing, idempotency tokens, and filenames created on multiple machines at once.
Choose how many
Pick 1, 5, 10, or 25 UUIDs. They're generated immediately.
Regenerate as needed
Hit Regenerate for a fresh batch — every UUID uses the browser's secure random source.
Copy what you need
Copy a single UUID, or use Copy all to grab the whole list.
Generated with crypto.randomUUID
The browser's own CSPRNG-backed UUID generator, not Math.random(). That distinction matters if the IDs are used anywhere an attacker could benefit from guessing the next one.
v4 UUIDs don't sort meaningfully
Because they're random, consecutive UUIDs are unrelated. If you need IDs that sort by creation time — which helps database index locality — look at UUIDv7 or ULID instead, which put a timestamp in the leading bits.
Not a secret by itself
A UUID is unguessable but not confidential: it appears in URLs, logs, and analytics. Use one as a capability token only when you're comfortable with it being visible in all of those places.
What version of UUID does it generate?
Version 4, variant 1 — the random variety, matching the format produced by crypto.randomUUID() and by the uuid npm package's v4 function.
Are the UUIDs generated on a server?
No. They're generated in your browser — there's no network request involved, so you can use the tool offline once the page has loaded.
Could two generated UUIDs ever collide?
The probability is vanishingly small. Version-4 UUIDs have 122 random bits; you'd need to generate billions before collision odds become meaningful.
Can I generate UUIDs in bulk?
Yes — pick 25 at a time and regenerate as often as you like. There's no rate limit because nothing leaves your device.
Are these suitable for database primary keys?
Yes. The birthday bound on 122 random bits sits around 2.3×10^18 values before a 50% collision chance — you'd need to mint a billion per second for decades. The usual reason teams avoid UUID keys is index performance, not uniqueness.
Every GhostDev tool runs entirely in your browser. Your file is never uploaded — there's no upload endpoint to send it to.