UUID Generator

Free Online UUID Generator

Our free UUID generator creates version-4 universally unique identifiers (UUIDs), from one up to 100 per batch, in standard, simple (no hyphens), or uppercase format. Typical uses are primary keys for seed scripts, fixture IDs for test data, and correlation IDs for tracing requests across services.

A UUID (Universally Unique Identifier) is a 128-bit value standardized by RFC 4122 that is designed to be unique across space and time without requiring a central registration authority. Version 4 UUIDs, which this tool generates, use random or pseudo-random numbers and are the most widely adopted variant in modern software development.

The UUIDs you generate are never sent to us or stored. Copy a single UUID from its row, or copy the whole batch at once to paste into your codebase, configuration file, or spreadsheet.

Key Features

• Generate 1 to 100 UUIDs in a single batch
• Three output formats: standard (with hyphens), simple (no hyphens), and uppercase
• RFC 4122 compliant version-4 UUID generation
• One-click copy for individual UUIDs
• Copy All button to grab every UUID at once
• Clean monospace display for easy reading
• Instant generation with no loading delay
• Generated UUIDs are never sent to us or stored
• Works on desktop, tablet, and mobile browsers
• Simple format drops the hyphens for systems that store UUIDs as 32 hex characters

How to Use the UUID Generator

1. Set the count: Enter how many UUIDs you need (from 1 up to 100).
2. Choose a format: Select Standard (e.g., 550e8400-e29b-41d4-a716-446655440000), Simple (no hyphens), or Uppercase.
3. Click Generate: Press the Generate button to create your UUIDs instantly.
4. Copy individual UUIDs: Click the copy icon next to any single UUID to copy it to your clipboard.
5. Copy all at once: Use the "Copy All" button to copy every UUID separated by newlines.

Use Cases

• Database primary keys: Use UUIDs as primary keys in relational and NoSQL databases to avoid collisions across distributed systems.
• API request IDs: Attach a UUID to each API request for end-to-end tracing and debugging in microservice architectures.
• Session tokens: Generate unique session identifiers for web application authentication and user tracking.
• File naming: Assign UUIDs as file names to prevent overwrites when storing user uploads.
• Test data generation: Quickly generate batches of unique IDs to populate test databases and mock environments.
• Distributed systems: Ensure globally unique object identifiers without a central coordination service.
• Configuration keys: Create unique identifiers for feature flags, experiment IDs, or deployment versions.

Frequently Asked Questions

Tips & Best Practices

• Use standard format for readability: The hyphenated format is easier to read and debug in logs and database queries.
• Use simple format for URLs: Remove hyphens when embedding UUIDs in URLs or file paths to keep them compact.
• Index UUID columns properly: In databases, use binary storage (BINARY(16)) instead of VARCHAR for better performance.
• Batch generate for testing: Use the count feature to generate up to 100 UUIDs at once for test data seeding.
• Avoid sequential patterns: Version 4 UUIDs are random by design, which is ideal for preventing enumeration attacks on public-facing IDs.