UUID Generator
Generate cryptographically secure UUID v4 identifiers
Click or press Space to generate
No UUIDs generated yet.
Click "Generate UUIDs" to create your first UUID.
How to Use This UUID Generator
Step-by-Step Guide
Configure Settings
Select how many UUIDs you need and choose your preferred format (standard, uppercase, no hyphens, or with braces).
Generate UUIDs
Click the "Generate UUIDs" button to create cryptographically secure UUID v4 identifiers.
Copy or Download
Copy individual UUIDs or all generated UUIDs to clipboard. Download as a text file for later use.
Use in Your Project
Paste the generated UUIDs into your database, application code, API requests, or configuration files.
Common Use Cases
Database Records
Generate unique IDs for database primary keys, ensuring no collisions across distributed systems.
API Development
Create unique identifiers for API resources, request IDs, and transaction tracking.
File & Session IDs
Generate unique names for uploaded files, session tokens, and temporary storage keys.
Distributed Systems
Create globally unique identifiers that can be generated independently across multiple servers.
Pro Tips for UUID Usage
- UUID v4 is recommended for most applications - it's completely random and doesn't require coordination
- For database indexing, consider storing UUIDs as BINARY(16) instead of VARCHAR(36) for better performance
- When generating multiple UUIDs for bulk operations, download them as a text file for easier import
- Use the "no hyphens" format when space is limited or for URL-friendly identifiers
- Always verify uniqueness when generating large batches for critical systems
UUID Formats & Standards
| Format Name | Pattern | Example | Use Case |
|---|---|---|---|
| Standard (Lowercase) | xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx | f47ac10b-58cc-4372-a567-0e02b2c3d479 | Most common, RFC 4122 compliant |
| Uppercase | XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX | F47AC10B-58CC-4372-A567-0E02B2C3D479 | Some legacy systems, easier to read |
| No Hyphens | xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx | f47ac10b58cc4372a5670e02b2c3d479 | Compact storage, URL parameters |
| With Braces | {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} | {f47ac10b-58cc-4372-a567-0e02b2c3d479} | Microsoft GUID format, .NET systems |
| URN Format | urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx | urn:uuid:f47ac10b-58cc-4372-a567-0e02b2c3d479 | URN identifiers, semantic web |
About UUID v4 (Random)
Characteristics
- All 122 bits are randomly generated
- Cryptographically secure random generation
- Can be generated independently anywhere
Technical Details
-
Version bits:
0100(binary) -
Variant bits:
10(RFC 4122) - Collision probability: Extremely low
Frequently Asked Questions
The probability of a UUID v4 collision is extremely low. To have a 50% chance of a single collision:
Mathematical Probability:
- • You would need to generate 2.71 quintillion UUIDs (2.71×10¹⁸)
- • At a rate of 1 billion UUIDs per second, it would take 85 years
- • The probability is about 1 in 2.71×10¹⁸ for any two UUIDs to be identical
For practical purposes, UUID v4 collisions are considered impossible in real-world applications.
Yes, our UUID generator uses the Web Cryptography API (crypto.getRandomValues()) which provides cryptographically secure random numbers.
Security Features
- • Uses browser's cryptographically secure RNG
- • No predictable patterns in generation
- • Suitable for security-sensitive applications
- • Complies with RFC 4122 UUID v4 specification
Privacy Guarantee
- • All generation happens locally in your browser
- • No data sent to our servers
- • No tracking or logging of generated UUIDs
- • Works completely offline
UUID v4 (random) is the most commonly used version. Here's when to use different UUID versions:
| Version | Type | When to Use |
|---|---|---|
| v1 | Time-based | When you need time-ordered UUIDs or MAC address inclusion |
| v3/v5 | Name-based (MD5/SHA-1) | When you need the same UUID for the same name/input |
| v4 | Random | Most use cases - databases, APIs, distributed systems |
| v6/v7 | New time-based | Future standards with better sortability |
Recommendation: Use UUID v4 for 90% of applications. It's simple, secure, and doesn't require coordination between systems.
Absolutely! UUIDs generated by this tool are suitable for production use. They are:
- RFC 4122 compliant - Follows the UUID standard specification
- Database-ready - Can be used as primary keys in PostgreSQL, MySQL, MongoDB, etc.
- Stateless generation - No coordination needed between servers
- High performance - Generation happens locally with no network latency
Database Tip: For better performance with UUIDs in databases, consider:
storing them as BINARY(16) instead of VARCHAR(36),
using UUID-specific data types if available (PostgreSQL's uuid type),
and creating appropriate indexes.
UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are essentially the same thing, with minor historical differences:
UUID (RFC 4122)
- • IETF standard (RFC 4122)
- • Typically lowercase (can be uppercase)
- • Used in Unix/Linux, web APIs, Java
- • Format:
xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
GUID (Microsoft)
- • Microsoft implementation
- • Typically uppercase
- • Often wrapped in braces
{} - • Used in Windows, .NET, COM
- • Format:
{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}
Practical difference: For most purposes, they are interchangeable. Our generator supports both formats (standard UUID and GUID with braces).
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