GUID V4 - Random-Based Identifier (Recommended)
GUID v4 is the most widely used random-based identifier. Learn about its structure, collision probability, advantages and why it is recommended for general-purpose applications.
How to Generate UUIDs in JavaScript
Generate UUIDs in JavaScript with crypto.randomUUID() for v4 and a package such as uuid for v7 when you need sortable identifiers.
Recommendation: use UUID v4 when you want zero dependencies in modern runtimes, and use UUID v7 when sortable identifiers matter more than pure randomness.
How to generate UUID v4 in JavaScript
const id = crypto.randomUUID();
console.log(id);How to generate UUID v7 in JavaScript
// npm install uuid
import { v7 as uuidv7 } from 'uuid';
const id = uuidv7();
console.log(id);Native support notes
- JavaScript uses UUID terminology across browser and Node-oriented packages.
- UUID v4 is native in modern environments with Web Crypto support.
- UUID v7 is typically package-based.
- Legacy browsers may require a fallback for
crypto.randomUUID().
Practical notes
- Prefer built-in Web Crypto when you only need v4 and your runtime supports it.
- Use one shared UUID library across frontend and backend packages when you standardize on v7.
- Read UUID v7 before introducing sortable IDs into database-heavy flows.
Frequently Asked Questions
It is available in modern browsers and runtimes, but older environments may still need a library fallback.
UUID v7 is useful when you want IDs that sort by creation time while still carrying random entropy.
Learn more
These articles expand on related concepts, formats and practical considerations.