UUID Generator
Generate UUID v1, v4, and v5 identifiers instantly with this free online UUID generator.
Create secure unique identifiers directly in your browser with no uploads or data storage.
UUID Generator
Generate UUID v1, v4 and v5 identifiers instantly. Create secure UUIDs directly in your browser.
0
v4
Ready
UUID v4 uses secure random values to generate identifiers.
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify data in software applications, databases, APIs, and distributed systems.
UUIDs are designed to minimize duplication, even when generated across different devices and systems independently.
Example UUID:
550e8400-e29b-41d4-a716-446655440000
UUID Versions Supported
This UUID generator supports multiple UUID versions for different use cases.
UUID v1
UUID v1 is based on timestamps and machine-related information.
It is useful when generation time ordering is important.
Best for:
- Legacy systems
- Timestamp-based identifiers
- Sequential UUID generation
UUID v4
UUID v4 uses secure random values to generate identifiers.
This is the most common and widely used UUID version today.
Best for:
- Web applications
- APIs
- Database identifiers
- General software development
UUID v5
UUID v5 generates deterministic UUIDs using SHA1 hashing with namespaces and names.
The same namespace and name combination always produces the same UUID.
Best for:
- Predictable identifiers
- Namespaced systems
- Stable generated IDs
How to use this UUID generator
- Select a UUID version
- Choose how many UUIDs to generate
- Click the generate button
- Copy or download the generated UUIDs
For UUID v5, enter a namespace and a name before generating.
UUID Format Explained
UUIDs contain 32 hexadecimal characters separated into 5 groups:
8-4-4-4-12
Example:
550e8400-e29b-41d4-a716-446655440000
Common Use Cases
- Database primary keys
- API tokens
- Session identifiers
- Distributed systems
- Software development
- Testing applications
UUID Version Comparison
| Version | Based On | Deterministic | Common Use |
|---|---|---|---|
| UUID v1 | Timestamp | No | Sequential systems |
| UUID v4 | Random values | No | General applications |
| UUID v5 | SHA1 namespace | Yes | Stable identifiers |
Why use UUIDs?
UUIDs allow developers to generate unique identifiers without relying on centralized systems or auto-incrementing database IDs.
This makes UUIDs ideal for scalable applications and distributed architectures.
Common Mistakes
- Confusing UUIDs with encryption
- Using predictable IDs instead of UUIDs
- Manually modifying UUID formats
- Assuming UUIDs are guaranteed to never collide
FAQ
Is this UUID generator free?
Yes, this tool is completely free to use online.
Are generated UUIDs secure?
Yes. UUID v4 values are generated using secure browser randomness.
Does this tool store generated UUIDs?
No. Everything runs locally in your browser.
What is the best UUID version?
UUID v4 is the most commonly recommended version for general use because it uses secure random generation.
When should I use UUID v5?
Use UUID v5 when you need deterministic UUIDs that always generate the same output for the same namespace and name.