UUID/GUID Generator
Generate random UUIDs and GUIDs
UUID/GUID Generator
Generate Multiple UUIDs
About UUID v4
UUID (Universally Unique Identifier) v4 uses random numbers to generate a 128-bit identifier. The format is: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where the '4' indicates version 4 and 'y' is one of 8, 9, A, or B. UUIDs are used for database primary keys, session IDs, and anywhere unique identifiers are needed without central coordination.
Privacy Notice
All UUIDs are generated locally in your browser using random numbers. No data is sent to any server.
Your Privacy is Protected
All processing happens entirely in your browser. No data is stored, transmitted, or tracked. Your information remains completely private and secure on your device.
About UUID Generator
Generate universally unique identifiers (UUIDs) instantly with our UUID generator tool. UUIDs (also called GUIDs - Globally Unique Identifiers) are 128-bit identifiers guaranteed to be unique across time and space, essential for databases, distributed systems, session IDs, and unique record keys. Our tool generates RFC 4122 compliant version 4 UUIDs using cryptographically strong random numbers, ensuring uniqueness even when generated simultaneously on different systems. Perfect for developers creating database primary keys, system administrators managing distributed systems, API developers generating unique tokens, and anyone needing guaranteed unique identifiers without centralized coordination.
Key Features
UUID v4 Generation
Generates RFC 4122 compliant version 4 UUIDs. Cryptographically random for maximum uniqueness guarantee.
Bulk Generation
Generate 1 to 1000 UUIDs at once. Perfect for bulk imports, testing, or seeding databases.
Multiple Format Options
Display UUIDs with or without hyphens, uppercase or lowercase. Match your system's UUID format requirements.
One-Click Copy
Copy single UUIDs or entire batch to clipboard. Use immediately in code, databases, or configuration files.
UUID Validation
Validate existing UUIDs to check format correctness. Ensure UUIDs meet RFC 4122 standards.
Format Conversion
Convert between UUID formats: hyphenated, non-hyphenated, uppercase, lowercase, braced. Standardize UUID formats.
How to Use UUID Generator
Select how many UUIDs to generate (1-1000)
Select how many UUIDs to generate (1-1000). Follow the tool interface to complete this step.
Choose UUID format (with/without hyphens, case)
Choose UUID format (with/without hyphens, case). Follow the tool interface to complete this step.
Click generate to create cryptographically random UUIDs
Click generate to create cryptographically random UUIDs. Follow the tool interface to complete this step.
View generated UUIDs in list format
View generated UUIDs in list format. Follow the tool interface to complete this step.
Copy individual UUIDs or entire batch
Copy individual UUIDs or entire batch. Follow the tool interface to complete this step.
Use UUIDs in your database, API, or application
Use UUIDs in your database, API, or application. Follow the tool interface to complete this step.
Optionally validate existing UUIDs for format compliance
Optionally validate existing UUIDs for format compliance. Follow the tool interface to complete this step.
Frequently Asked Questions
What is a UUID?
UUID (Universally Unique Identifier) is a 128-bit number, typically displayed as 32 hexadecimal digits in format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx. The '4' indicates version 4 (random). UUIDs are designed to be unique without central registration.
How unique are UUIDs? Can they collide?
Version 4 UUIDs have 122 random bits. Probability of collision is astronomically low - generating 1 billion UUIDs per second for 100 years has 50% collision chance of only 0.0000000006%. For practical purposes, UUIDs are unique.
What's the difference between UUID and GUID?
They're essentially the same. UUID is the RFC 4122 standard term. GUID (Globally Unique Identifier) is Microsoft's term. Both refer to 128-bit unique identifiers with the same format.
Should I use UUIDs or auto-increment IDs?
Auto-increment IDs: simpler, sequential, smaller (4-8 bytes), better for single database. UUIDs: work across distributed systems, can generate offline, no coordination needed, larger (16 bytes), don't expose record count. Choose based on architecture.
Can I store UUIDs in databases?
Yes! Most databases have UUID/GUID types: PostgreSQL (UUID), MySQL (BINARY(16) or CHAR(36)), SQL Server (UNIQUEIDENTIFIER), MongoDB (BinData). Store as binary for space efficiency or string for readability.
Are UUIDs secure for tokens or secrets?
Version 4 UUIDs are random and unpredictable, suitable for non-sensitive identifiers. For authentication tokens or cryptographic keys, use dedicated secure token generation (crypto libraries). UUIDs are identifiers, not security tokens.
What UUID version should I use?
Version 4 (random) is most common and suitable for most use cases. Version 1 includes timestamp and MAC address (privacy concern). Version 5 is name-based (deterministic). For general purpose, use v4.
How do I format UUIDs for URLs?
Remove hyphens for cleaner URLs: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx instead of xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. Both are valid UUIDs. Use our formatter to convert between formats.
Use Cases
- Database Primary Keys: Use UUIDs as primary keys in distributed databases. Unlike auto-increment IDs, UUIDs don't require centralized coordination and avoid collisions across database instances.
- API Request Tracking: Generate unique request IDs for API calls, tracking requests across microservices, logging, and debugging distributed systems.
- Session and Token Generation: Create unique session IDs, authentication tokens, or temporary identifiers. UUIDs are unpredictable and suitable for security-sensitive identifiers.
- File and Resource Naming: Generate unique filenames for uploads, prevent filename collisions, create unique resource identifiers for cloud storage.
- Testing and Development: Generate test data with unique IDs, seed databases with UUID keys, create mock data for development and QA environments.