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UUID Generator

Generate random UUID v4 values for databases, APIs, and unique identifiers.

🆔 Generate UUIDs

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UUID Generator — Free, Instant Unique IDs

Generate UUID (Universally Unique Identifier) v4 strings instantly — for free, with no account required. Generate a single UUID or bulk-generate hundreds at once. UUIDs are essential in software development for identifying database records, API resources, session tokens, and distributed system components. A UUID (also called GUID in Microsoft contexts) is a 128-bit identifier formatted...

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Generate UUID (Universally Unique Identifier) v4 strings instantly — for free, with no account required. Generate a single UUID or bulk-generate hundreds at once. UUIDs are essential in software development for identifying database records, API resources, session tokens, and distributed system components.

A UUID (also called GUID in Microsoft contexts) is a 128-bit identifier formatted as 32 hexadecimal characters in 5 groups: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. Version 4 UUIDs are randomly generated, making the probability of collision astronomically small — practical uniqueness is guaranteed even across distributed systems.

When to Use UUIDs

  • Database primary keys: Use instead of auto-incrementing integers to avoid sequential ID exposure
  • API resource IDs: REST APIs commonly use UUIDs as resource identifiers
  • Session tokens: Generate unique session identifiers for user authentication
  • File naming: Create collision-free unique filenames for uploads
  • Distributed systems: Generate IDs across multiple servers without coordination

How to Generate a UUID — Step by Step

  1. Click Generate: Click "Generate UUID" to create a new UUID v4 instantly.
  2. Copy: Click "Copy" to copy the UUID to your clipboard.
  3. Bulk generate: Enter a number and click "Bulk Generate" for multiple UUIDs at once.
  4. Format options: Choose between standard UUID format, uppercase, or without hyphens.
  5. Use in code: Paste directly into your code, database, or configuration.

❓ Frequently Asked Questions

What is UUID v4?

UUID v4 is a randomly generated universally unique identifier. Unlike v1 (time-based) or v5 (name-based), v4 is generated from random numbers, making it ideal for most use cases.

Are two UUIDs ever the same?

In practice, no. The probability of generating a duplicate UUID v4 is astronomically small — roughly 1 in 5.3 × 10^36. They are considered practically unique.

What is the difference between UUID and GUID?

They are the same thing. GUID (Globally Unique Identifier) is Microsoft's term for UUID, following the same standard and format.

Can I use UUIDs as database primary keys?

Yes — UUIDs are commonly used as primary keys, especially in distributed systems. Note that random UUID v4 keys can fragment database indexes; consider UUID v7 (time-ordered) for high-performance scenarios.

Is this tool free?

Yes, 100% free with no account required.

Are the generated UUIDs truly random?

Yes — they use your browser's cryptographically secure random number generator (crypto.getRandomValues) for high-quality randomness.

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