UUID Generator
Generate secure random UUID v4 identifiers instantly. Perfect for database IDs, API keys, authentication tokens, and distributed systems.
Generated UUID
d059d33b-a487-4290-bec4-e903892f6412Bulk UUID Generation
UUID Format
123e4567-e89b-12d3-a456-426614174000Introduction
Free Online UUID Generator
The UUID Generator creates secure, random UUID v4 identifiers instantly. Whether you're a developer needing database primary keys, a system architect coordinating distributed systems, or a security engineer generating tokens, this tool provides cryptographically secure unique identifiers without installing software.
All UUIDs are generated locally in your browser using the Web Crypto API — they are never stored, transmitted, or logged anywhere, ensuring complete privacy and security.
About the tool
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier that is unique across both space and time. It's represented as 32 hexadecimal digits displayed in 5 groups separated by hyphens (8-4-4-4-12), totaling 36 characters.
UUID v4 (the version we generate) uses cryptographically secure random numbers, making collisions practically impossible. This makes UUIDs ideal for distributed systems where central coordination isn't possible.
Benefits
Why Use Our UUID Generator?
Cryptographically Secure
Uses Web Crypto API for true random number generation — the same technology used by browsers.
Instant Generation
Generate UUIDs in milliseconds with just one click.
Bulk Generation
Generate up to 100 UUIDs at once for testing and development.
Offline Support
Once loaded, the tool works without internet connection.
Technical reference
UUID Versions Explained
Version 1 (Time-based)
Generated using timestamp and MAC address
Can reveal creation time and origin
Best for: Systems requiring sortable identifiers
Version 2 (DCE Security)
Time-based with POSIX UID/GID
Limited use, can reveal system info
Best for: Legacy DCE systems
Version 3 (Name-based - MD5)
Generated from namespace and name using MD5
Deterministic, not random
Best for: Consistent IDs for same input
Version 4 (Random)
RecommendedGenerated from cryptographically secure random numbers
Unpredictable and secure
Best for: Most applications requiring unique IDs
Version 5 (Name-based - SHA1)
Generated from namespace and name using SHA1
Deterministic, not random
Best for: Consistent IDs with stronger hashing
Target users
Who Should Use This Tool?
Backend Developers
Generate unique IDs for database records and APIs
Frontend Developers
Create client-side unique identifiers
Mobile Developers
Generate device and session identifiers
DevOps Engineers
Track requests across distributed systems
Security Engineers
Generate secure tokens and identifiers
Students
Learn about unique identifier standards
Practical applications
Real-World Use Cases
Database Primary Keys
Use as unique identifiers instead of auto-incrementing integers
CREATE TABLE users (id UUID PRIMARY KEY)API Request Tracking
Track requests across distributed systems
X-Request-ID: 123e4567-e89b-12d3Session Tokens
Generate unique session identifiers for users
session_id = uuid.v4()Mobile App Identifiers
Unique device or installation IDs
device_id = crypto.randomUUID()Comparison
Why Choose AttachAD?
| Feature | AttachAD | Manual Generation | UUID Libraries |
|---|---|---|---|
| Free to Use | — | ||
| Browser Based | — | — | |
| No Installation | — | ||
| Mobile Friendly | — | — | |
| Offline Support | |||
| Cryptographically Secure | — | ||
| Bulk Generation | — | ||
| No Registration | |||
| Copy to Clipboard | — | — | |
| UUID Format Guide | — | — |
FAQ
Frequently Asked Questions
A UUID (Universally Unique Identifier) is a 128-bit identifier that is unique across both space and time. It's represented as 32 hexadecimal digits displayed in 5 groups separated by hyphens (8-4-4-4-12), totaling 36 characters. UUIDs are designed to be unique without requiring central coordination, making them ideal for distributed systems.
Explore more
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Need a unique identifier?
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