UUID vs GUID: Understanding Unique Identifiers

What Are UUIDs and GUIDs?

UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are essentially the same thing - 128-bit numbers used to uniquely identify information in computer systems.

The Anatomy of a UUID

A standard UUID looks like this:

550e8400-e29b-41d4-a716-446655440000

It consists of:

UUID Versions

Version 1: Timestamp + MAC Address

Generated using the current timestamp and the computer's MAC address. Unique but can reveal information about when/where it was created.

Version 4: Random (Most Common)

Generated using random or pseudo-random numbers. This is what our UUID Generator creates.

Version 5: Name-based (SHA-1)

Generated by hashing a namespace identifier and name.

When to Use UUIDs

Database Primary Keys

CREATE TABLE users (

id UUID PRIMARY KEY DEFAULT gen_random_uuid(),

name VARCHAR(100)

);

Distributed Systems

UUIDs can be generated independently without coordination between servers.

File Naming

Prevent conflicts when multiple users upload files simultaneously.

Session Tokens

Create unique session identifiers for user authentication.

UUID vs Auto-Increment IDs

Generate UUIDs Instantly

Use our UUID Generator to create:

Other Developer Tools

Conclusion

UUIDs are essential for modern software development. Whether you need one or hundreds, our free UUID Generator has you covered.