UUID Generator – Complete Guide & Free Online Tool

A UUID generator creates Universally Unique Identifiers — 128-bit values used to uniquely identify records, files and resources. It can produce many at once. Free online tool included.

Published 2026-09-13

In this guide
  1. What is UUID Generator?
  2. What is a UUID?
  3. Why use UUIDs?
  4. Key Features
  5. Examples
  6. Common Use Cases
  7. Tips & Best Practices
  8. Limitations
  9. Related Tools
  10. External Resources

What is UUID Generator?

A UUID generator creates Universally Unique Identifiers — 128-bit values used to uniquely identify records, files and resources. It can produce many at once.

What is a UUID?

A UUID is a 128-bit number formatted as 32 hexadecimal digits in groups of 8-4-4-4-12, e.g. 550e8400-e29b-41d4-a716-446655440000. Version 4 uses random values.

Why use UUIDs?

UUIDs avoid collisions across databases and systems, are safe to generate offline, and do not reveal sequential information.

Key Features

• Cryptographically random v4 UUIDs • Generate many at once • Copy or download

Examples

• 550e8400-e29b-41d4-a716-446655440000

Common Use Cases

• Database primary keys • API resource IDs • Session tokens

Tips & Best Practices

• Use v4 for general unique identifiers.

Limitations

• Collisions are astronomically unlikely but not impossible.

Related Tools

Explore other developer tools: [Developer Tools](/categories/developer).

Related tools: [random-string](/tools/random-string), [hash-generator](/tools/hash-generator), [invoice-number-generator](/tools/invoice-number-generator).

External Resources

RFC 4122: UUID

Related Tools

Random String Generator Generate random alphanumeric strings. Generators Use Tool →
Hash Generator Generate SHA-1, SHA-256 and SHA-512 hashes of your text. Developer Use Tool →
Invoice Number Generator Generate sequential invoice numbers for your business. Generators Use Tool →

Frequently Asked Questions

What is a UUID?
A 128-bit universally unique identifier used to uniquely identify resources.
Are these truly random?
Yes, they are generated using the browser\
Can I generate multiple at once?
Yes, up to 100 at a time.
Is it free?
Yes, and it runs locally.

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