Attachad

UUID GeneratorGenerate Secure Random UUIDs

Generate secure random UUID v4 identifiers instantly. Perfect for database IDs, API keys, authentication tokens, and distributed systems.

✓ UUID v4✓ Cryptographically Secure✓ Bulk Generation✓ 100% Free

Generated UUID

2aad2adf-80de-4e7a-a320-9c26f94c3dda

Bulk UUID Generation

UUID Format

123e4567-e89b-12d3-a456-426614174000
TimeLow
8 chars
TimeMid
4 chars
Version
4 chars
Variant
4 chars
Node
12 chars
Version:4 (Random)
Variant:RFC 4122
Length:36 characters
Entropy:122 bits

What is a UUID?

A UUID (Universally Unique Identifier)is a 128-bit identifier that is unique across both space and time. UUID v4 (the version we generate) uses cryptographically secure random numbers, making collisions practically impossible.

Developers use UUIDs for database primary keys, API request tracking, session identifiers, distributed system coordination, and any scenario requiring unique identification without central coordination.

UUID Versions Explained

Version 1 (Time-based)

Generated using timestamp and MAC address. Can reveal creation time and origin.

Version 3 (Name-based - MD5)

Generated from a namespace and name using MD5 hashing.

Version 4 (Random) - Recommended

Generated from random numbers. Best for most applications requiring uniqueness without predictability.

Version 5 (Name-based - SHA1)

Generated from a namespace and name using SHA1 hashing.

Common Use Cases for UUIDs

🗄️ Database Primary Keys

Use as unique identifiers instead of auto-incrementing integers

🔗 API Request Tracking

Track requests across distributed systems

🔐 Session Tokens

Generate unique session identifiers for users

📱 Mobile App Identifiers

Unique device or installation IDs

Frequently Asked Questions

What's the difference between UUID and GUID?

GUID is Microsoft's implementation of UUID. They are functionally identical and follow the same standard (RFC 4122).

Are UUIDs truly unique?

UUID v4 uses 122 random bits, making the probability of collision extremely low. You'd need to generate billions of UUIDs for a non-zero chance of collision.

Is this UUID generator free?

Yes! Attachad's UUID generator is completely free with no limits or hidden fees.

Can UUIDs be predicted?

Our generator uses cryptographically secure random number generation (crypto.randomUUID()), making UUIDs unpredictable and secure.

Is my data stored?

No, UUIDs are generated locally in your browser and never stored or transmitted anywhere.

Need a Unique Identifier?

Generate a secure UUID now — it's free, fast, and private.