UUID Generator

What this tool does

The UUID Generator creates Universally Unique Identifiers (UUIDs), specifically UUID version 4, which are 128-bit identifiers used to uniquely identify information in computer systems. UUIDs are standardized by RFC 4122 and are widely used in distributed systems, databases, and applications where unique identifiers are required.

This tool generates cryptographically random UUIDs that are virtually guaranteed to be unique. It supports generating single UUIDs or bulk UUIDs in batches, making it useful for testing, development, and system integration scenarios where multiple unique identifiers are needed.

UUIDs are displayed in their standard format: 8-4-4-4-12 hexadecimal digits separated by hyphens (e.g., 550e8400-e29b-41d4-a716-446655440000). The tool ensures each generated UUID follows the UUID v4 specification, which uses random or pseudo-random numbers.

When to use it

Database Primary Keys: Generate unique primary keys for database records when auto-increment IDs aren't suitable.

Distributed Systems: Create unique identifiers for distributed systems where centralized ID generation isn't possible.

API Development: Generate unique identifiers for API resources, request IDs, or transaction IDs.

Testing: Create test data with unique identifiers for unit tests, integration tests, or performance testing.

Session Management: Generate session IDs or user identifiers for web applications.

File Naming: Create unique file names or identifiers for uploaded files or generated documents.

Event Tracking: Generate unique event IDs for analytics, logging, or event tracking systems.

How to use it

1. Set Count: Enter the number of UUIDs you want to generate (1-100). Default is 1.

2. Generate: Click the "Generate" button to create UUIDs.

3. View Results: All generated UUIDs are displayed in the output area, one per line.

4. Copy: Use the copy button to copy all UUIDs to your clipboard for use in your applications.

5. Reset: Use the reset button to clear the count and generated UUIDs.

Example

Single UUID:

a1b2c3d4-e5f6-4789-a012-3456789abcde

Bulk UUIDs (5):

a1b2c3d4-e5f6-4789-a012-3456789abcde
b2c3d4e5-f6a7-4890-b123-456789abcdef
c3d4e5f6-a7b8-4901-c234-56789abcdef0
d4e5f6a7-b8c9-4012-d345-6789abcdef01
e5f6a7b8-c9d0-4123-e456-789abcdef012

Common mistakes

Assuming Sequential Order: UUIDs are random and don't follow sequential patterns. Don't rely on them for ordering.

Using for Sorting: UUIDs are not suitable for sorting or range queries. Use timestamps or sequential IDs if ordering is needed.

Storing as Strings: While UUIDs are often displayed as strings, store them efficiently in databases (as UUID type or binary format).

Case Sensitivity: UUIDs are case-insensitive, but it's best practice to use lowercase consistently.

Version Confusion: This tool generates UUID v4 (random). Other versions (v1 timestamp-based, v3/v5 name-based) have different use cases.

Security Misuse: While UUIDs are unique, they're not secret. Don't use them for security tokens or authentication without additional security measures.

Tips for better results

Use Appropriate Count: Generate only as many UUIDs as you need. For bulk operations, generate in batches rather than extremely large numbers.

Database Storage: When storing UUIDs in databases, use native UUID types when available for better performance and storage efficiency.

Indexing: UUIDs can be indexed, but random UUIDs (v4) may cause index fragmentation. Consider UUID v1 for better index performance if ordering isn't critical.

API Integration: Use generated UUIDs for API resource identifiers, ensuring they're properly formatted and validated.

Testing: Generate UUIDs for test data to ensure your application handles unique identifiers correctly.

Documentation: Include generated UUIDs in API documentation as examples of expected identifier formats.

Validation: Always validate UUID format in your applications to ensure they match the UUID specification.

FAQ

What is a UUID? UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify information. UUID v4 uses random numbers for uniqueness.

How many UUIDs can I generate? You can generate 1 to 100 UUIDs at a time. For larger batches, generate multiple times or use command-line tools.

Are UUIDs really unique? UUID v4 uses cryptographically random numbers, making collisions extremely unlikely (virtually impossible in practice).

Can I use UUIDs for sorting? No, UUIDs are random and not suitable for sorting. Use timestamps or sequential IDs if ordering is needed.

What version of UUID does this generate? This tool generates UUID version 4, which uses random or pseudo-random numbers.

Is there a size limit? The tool can generate up to 100 UUIDs at a time. Each UUID is 36 characters long (32 hex digits + 4 hyphens).

Can I use this offline? Yes, once the page is loaded, UUID generation happens entirely in your browser and works offline.

Are UUIDs secure? UUIDs are unique but not secret. They're not suitable for security tokens without additional encryption or signing.

Can I customize the format? This tool generates standard UUID v4 format. For custom formats, you would need specialized tools or libraries.

What's the difference between UUID versions? UUID v1 uses MAC address and timestamp, v3/v5 use namespaces and names, v4 uses random numbers. This tool generates v4.