100% client-side, nothing leaves your browser
Free UUID Generator
Generate random UUIDs instantly in your browser. Create secure version 4 UUIDs locally with no registration, no tracking, and no data leaving your device.
No UUIDs generated yet. Click "Generate New UUIDs" to start.
Validate a UUID
How this UUID generator works
Choose your UUID settings
Pick a version, a quantity, and a formatting style that matches what your project expects.
Your browser creates them locally
Cryptographically random UUIDs are generated on your device using the Web Crypto API, entirely offline.
Copy or download instantly
Copy a single value, copy the whole batch, or download everything as a plain text file.
Privacy note: every UUID is generated locally in your browser. Nothing you enter or generate here is ever uploaded, logged, or transmitted anywhere.
Where UUIDs get used
A few common situations where a UUID is the right tool for the job.
Database IDs
Assign primary keys that stay unique across tables, shards, or replicas without a shared auto-increment counter.
API development
Generate request IDs, API keys, or resource identifiers that clients can reference without collisions.
Software testing
Create disposable, unique test fixtures and identifiers that won't clash between test runs.
Distributed systems
Coordinate identifiers across independent services or nodes with no central ID authority required.
Temporary identifiers
Tag sessions, uploads, or short-lived resources with an ID that's simple to generate on demand.
Mock data generation
Populate seed data, fixtures, or sample datasets with realistic-looking unique IDs quickly.
Frequently asked questions
What is a UUID?
A UUID, or universally unique identifier, is a 128-bit value used to identify information without needing a central authority to assign it. It's typically written as 32 hexadecimal digits grouped into five sections separated by hyphens, such as 550e8400-e29b-41d4-a716-446655440000.
Are UUIDs unique?
For all practical purposes, yes. A random version 4 UUID has 122 bits of randomness, meaning the odds of two generators ever producing the same value by chance are astronomically small, even across billions of IDs generated independently.
What version of UUID does this tool generate?
This tool defaults to version 4, which is fully random and the most widely used variant for general-purpose IDs. It also supports version 1, which encodes a timestamp and a random node identifier, and version 7, which encodes a sortable timestamp alongside random bits.
Can someone track generated UUIDs?
No tracking is built into a UUID itself. A version 4 UUID reveals nothing about when or where it was created. Version 1 and version 7 UUIDs do encode a timestamp, so avoid them if you specifically need to hide the creation time of an identifier.
Does this UUID generator store my data?
No. Every UUID is generated locally in your browser using JavaScript and the Web Crypto API. Nothing is sent to a server, logged, or stored anywhere, and the tool keeps working the same way even if you disconnect from the internet after the page loads.
Can UUIDs replace database IDs?
Yes, and many systems use them for exactly that. UUIDs avoid collisions across distributed databases and services without a shared counter, though they take more storage space than a simple integer and can fragment certain database indexes if not chosen carefully.
Are UUIDs secure?
A version 4 UUID generated with a cryptographically secure random source is not practically guessable, which makes it reasonable for use as a hard-to-guess identifier. It is not, however, a substitute for proper authentication or access control on sensitive resources.
What is the difference between UUID and GUID?
GUID stands for globally unique identifier and is Microsoft's name for the same underlying concept as a UUID. The two terms describe the same 128-bit structure and are used interchangeably in practice, though GUID appears more often in Windows and .NET contexts.
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