UUID Generator
Generate unique universal identifiers (v1, v4) for your development projects instantly.
Generated Result
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information in computer systems. Also known as GUIDs (Globally Unique Identifiers), UUIDs are standardized by the Open Software Foundation (OSF) as part of the Distributed Computing Environment (DCE). The formal definition is described in RFC 4122.
UUIDs are typically represented as 32 hexadecimal digits, displayed in five groups separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters (32 alphanumeric characters and 4 hyphens). For example: 550e8400-e29b-41d4-a716-446655440000
The probability of generating duplicate UUIDs is so low that it's considered negligible for practical purposes. With version 4 UUIDs (random), there are approximately 5.3 × 10³⁶ (or 2¹²²) possible UUIDs, making collision virtually impossible.
infoHow it works
Choose Configuration
Select the UUID version (v1 or v4) and specify the quantity you need. Version 4 is recommended for most use cases as it provides maximum randomness and privacy without exposing hardware information.
Click Generate
Press the button to instantly create unique identifiers using cryptographically secure algorithms. All generation happens in your browser - no data is sent to any server.
Copy & Use
Use the 'Copy all' feature to grab the results and paste them into your application, database, or wherever you need unique identifiers. Each UUID is guaranteed to be unique.
helpFrequently Asked Questions
Are these UUIDs safe for production?expand_more
What is the difference between v1 and v4?expand_more
Can I generate millions of UUIDs?expand_more
Is there a limit on how many I can generate?expand_more
What is the probability of UUID collision?expand_more
Can UUIDs be used as database primary keys?expand_more
Are UUIDs sortable?expand_more
How are UUIDs different from regular random numbers?expand_more
Can I decode information from a UUID?expand_more
Are UUIDs URL-safe?expand_more
What programming languages support UUIDs?expand_more
Should I use UUID v1 or v4?expand_more
How do I store UUIDs in databases?expand_more
Can UUIDs be casefold or how should I compare them?expand_more
Are there alternatives to UUID?expand_more
lightbulbCommon Use Cases
storageDatabase Primary Keys
UUIDs are ideal for distributed databases where multiple systems need to generate IDs independently without coordination or conflict.
keySession Identifiers
Create unique session IDs for web applications, ensuring each user session is uniquely tracked without predictable patterns.
receipt_longTransaction IDs
Generate unique identifiers for financial transactions, orders, or any business process that requires traceable unique references.
cloudDistributed Systems
Enable microservices and distributed applications to generate IDs without central coordination, avoiding bottlenecks and single points of failure.
descriptionFile Naming
Create unique filenames for uploads, temporary files, or cached resources, preventing naming conflicts in shared storage systems.
apiAPI Request IDs
Track individual API requests across distributed systems for debugging, monitoring, and correlation of logs and metrics.
verifiedBest Practices
Choose the Right Version
Use UUID v4 for general purposes where privacy is important. Use v1 only when you specifically need chronological ordering or timestamp information embedded in the identifier.
Store Efficiently
When storing UUIDs in databases, use native UUID data types or binary storage (16 bytes) rather than string representation (36 characters) to save space and improve index performance.
Validate Input
Always validate UUID format when accepting them as input. Use regex patterns or built-in validation functions in your programming language to ensure format correctness.
Use Lowercase
Standardize on lowercase representation for UUIDs throughout your application for consistency. While UUIDs are case-insensitive, using a consistent case prevents confusion and comparison issues.
Consider Indexing Strategy
Random UUIDs (v4) can cause index fragmentation in databases due to their random nature. For high-volume insertions, consider using sequential UUIDs (like v1) or database-specific solutions like PostgreSQL's uuid-ossp extension with uuid_generate_v1mc().
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