UUID GENERATOR

Generate universally unique identifiers (v4) instantly in your browser.
Cryptographically Secure • Version 4 • 100% Free

Free UUID Generator for UUID v4 and GUID Values

This UUID Generator creates random Version 4 UUIDs instantly in your browser. You can use the generated identifier for database records, app objects, API testing, filenames, sessions, mock data, distributed systems, logs, and development workflows that need unique values.

A UUID is useful when you need an identifier that can be created independently without asking a central database or server for the next number. Click Generate New UUID to create a fresh value, then use Copy UUID to move it into your project.

How to Use This UUID Generator

  1. Generate a UUID. A UUID is created automatically when the page loads, and you can click Generate New UUID whenever you need another one.
  2. Review the output. The generated UUID appears in the standard 8-4-4-4-12 format.
  3. Copy the UUID. Click Copy UUID to place the generated identifier on your clipboard.
  4. Use it in your workflow. Paste the UUID into your database, app, test data, API payload, file name, documentation, or codebase.

UUID Format Example

A standard UUID is shown as 32 hexadecimal characters separated by hyphens into five groups. UUID v4 values include random bits and specific version/variant markers.

Example UUID

550e8400-e29b-41d4-a716-446655440000

Standard Pattern

xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

Helpful note: UUIDs are designed for uniqueness, not secrecy. Do not treat a UUID as a password, private token, or security credential unless your system adds proper authentication and access control around it.

What This UUID Tool Can Do

Generate UUID v4

Create random Version 4 UUIDs for identifiers, records, sessions, files, APIs, object IDs, logs, and test data.

Copy in One Click

Use the Copy UUID button to quickly move the generated identifier into your editor, spreadsheet, database, documentation, or app.

Run in Your Browser

The UUID is generated in your browser using the built-in Web Crypto API where supported, so the tool is fast and simple to use.

Use for GUID Workflows

UUID and GUID are commonly used interchangeably, so this tool is also useful when a system asks for a GUID-style value.

Common Uses for UUIDs

  • Database primary keys: Create unique identifiers for records in SQL, NoSQL, and distributed databases.
  • API testing: Generate sample IDs for mock requests, responses, objects, users, products, orders, or events.
  • File naming: Reduce filename collisions when storing uploads, exports, logs, or generated files.
  • Session and object tracking: Assign unique IDs to sessions, transactions, jobs, messages, or application objects.
  • Distributed systems: Create identifiers independently across services without relying on one central counter.
  • Test data: Quickly create realistic unique-looking IDs for prototypes, QA, demos, and seed data.

UUID vs GUID vs Sequential ID

Identifier Type Best For Key Difference
UUID Distributed systems, databases, apps, APIs, logs, test data, and records that need unique values. A broadly used standard for unique identifiers, commonly represented in 8-4-4-4-12 format.
GUID Microsoft ecosystems, Windows tools, .NET projects, databases, and systems that ask for GUID values. Often treated as Microsoft's terminology for UUID-style identifiers.
Sequential ID Simple local databases, ordered records, small apps, and cases where auto-incrementing values are acceptable. Easy to read and sort, but can expose record counts and usually needs central coordination.

Who This UUID Generator Is For

Developers

Generate IDs for frontend, backend, database, API, testing, logging, queue, and distributed system workflows.

Database Admins

Create UUID-style values for records, imports, seed data, tables, references, and system identifiers.

Students

Learn what UUIDs look like and practice using unique identifiers in programming, database, and web development projects.

QA and Product Teams

Create sample identifiers for testing, bug reports, prototypes, documentation, API examples, and workflow demos.

Best Practices When Using UUIDs

  • Use UUIDs for uniqueness, not secrecy: A UUID is an identifier, not a password or secure access token.
  • Store them consistently: Decide whether your system will store UUIDs as strings, native UUID types, or binary values.
  • Keep formatting predictable: Most systems expect lowercase UUIDs with hyphens in the standard format.
  • Validate user-provided UUIDs: If users or external systems submit UUIDs, validate the format before storing or using them.
  • Consider database performance: UUIDs are useful, but random identifiers can affect indexing patterns in some database designs.

Frequently Asked Questions

What is a UUID?

UUID stands for Universally Unique Identifier. It is a 128-bit identifier commonly used to label records, files, sessions, objects, events, and other data in software systems.

What does this UUID Generator create?

This tool generates random Version 4 UUIDs in the standard 8-4-4-4-12 format, such as xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.

What is the difference between UUID and GUID?

UUID and GUID are often used interchangeably. GUID is commonly associated with Microsoft's terminology, while UUID is the broader standard term.

Is a UUID v4 guaranteed to be unique?

A UUID v4 is randomly generated and designed to make duplicates extremely unlikely. In normal development and database use, the chance of collision is considered practically negligible.

Is this UUID Generator secure?

The generator runs in your browser using the crypto.randomUUID() API where supported. The UUID is created locally while you use the page.

Does this UUID tool send data to a server?

No. The UUID generation happens in your browser. The generated UUID does not need to be sent to a server to be created.

When should I use a UUID?

UUIDs are useful for database primary keys, file names, session IDs, API records, distributed systems, test data, object identifiers, and any workflow that needs unique values.

Can I use this UUID Generator for databases?

Yes. UUIDs are commonly used as identifiers in SQL databases, NoSQL databases, logs, APIs, and distributed applications.