UUID Generator
Generate RFC 4122 compliant UUIDs (v1, v3, v4, v5) for databases, APIs, and distributed systems.
UUID Versions:
- v1 (Time-based): Based on MAC address and current time
- v3 (MD5): MD5 hash of namespace and name
- v4 (Random): Random generation (most common)
- v5 (SHA1): SHA1 hash of namespace and name
Use Cases: Database IDs, session tokens, request tracking, distributed systems
How to Use UUID Generator
- Select the UUID version (v1, v3, v4, or v5)
- Specify the number of UUIDs to generate (max 1000)
- Click "Generate UUID" button
- Copy individual UUIDs or all at once
- Use the UUIDs in your application
UUID Versions Explained
Version 1 (Time-based)
Generated from timestamp and MAC address
- ✓ Sortable by creation time
- ✓ Useful for ordered records
- ⚠️ MAC address exposed (privacy concern)
Version 4 (Random)
Randomly generated (most common)
- ✓ Simple and fast
- ✓ No privacy concerns
- ✓ Recommended for most use cases
Version 3 (MD5 Hash)
Generated from namespace and name using MD5
- ✓ Deterministic (same input = same UUID)
- ✓ Useful for consistent IDs
Version 5 (SHA-1 Hash)
Generated from namespace and name using SHA-1
- ✓ More secure than v3
- ✓ Deterministic like v3
UUID Use Cases
Database Primary Keys
Perfect for primary keys in distributed databases where auto-increment IDs are problematic.
API Request Tracking
Track requests across microservices and distributed systems with unique identifiers.
Session Management
Generate unique session IDs that are impossible to guess or predict.
File Naming
Create unique file names for uploads without collision risks.
Frequently Asked Questions
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify objects or entities in distributed systems.
When should I use UUID v4?
v4 (random) is recommended for most use cases - it's simple, fast, and widely supported without requiring namespace information.
What about UUID v1?
v1 includes timestamp and MAC address, useful for sortability but has privacy implications (MAC address exposed).
Can UUIDs collide?
Collision probability is astronomically small - for practical purposes, UUIDs are unique. v4 has 2^122 possibilities.
Are UUIDs database-friendly?
Yes, UUIDs work great as primary keys in databases. Some databases optimize UUID storage (like PostgreSQL's uuid type).
What's the format of a UUID?
Standard format: 8-4-4-4-12 hexadecimal digits (e.g., f47ac10b-58cc-4372-a567-0e02b2c3d479)
Can I generate UUID v3/v5 with custom namespaces?
This tool generates standard v3/v5. For custom namespaces, use specialized UUID libraries.
Are these UUIDs cryptographically secure?
v4 provides good randomness. For cryptographic purposes, use dedicated cryptographic random generators.
How many UUIDs can I generate?
You can generate up to 1000 at once in this tool.
Is my data private?
Yes, UUID generation happens entirely in your browser. Nothing is sent to any server.
About UUID Generator
UUIDs are essential for building distributed systems, microservices, and applications that need unique identifiers across multiple systems without central coordination.
Key Features
- Perfect for database primary keys
- Essential for API request tracking
- Used in distributed systems and cloud applications
- Unique across time and space without coordination
- 100% browser-based - no server needed
- RFC 4122 compliant