How to generate UUIDs in Node.js

Native (Node.js 19+): const id = crypto.randomUUID() — no package needed, cryptographically secure UUID v4. With the uuid package: npm install uuid; const { v4: uuidv4 } = require('uuid'); const id = uuidv4(). For older Node.js: require('crypto').randomBytes(16) and manually format as UUID. In browsers and Deno, crypto.randomUUID() is also available globally. The native method is fastest and has zero dependencies.

// Node.js — generate UUIDs
import { randomUUID } from "crypto";

// Built-in (Node.js 14.17+) — UUID v4
const id = randomUUID();
console.log(id); // "f47ac10b-58cc-4372-a567-0e02b2c3d479"

// Browser — crypto.randomUUID()
const browserId = crypto.randomUUID();

// With uuid package (for v1, v3, v5)
import { v4, v5, validate } from "uuid";
console.log(v4());                        // random UUID
console.log(v5("example.com", v5.DNS));   // deterministic
console.log(validate("not-a-uuid"));       // false

UUID patterns in Node.js applications

Express route with UUID validation: app.get('/users/:id', (req, res) => { if (!/^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i.test(req.params.id)) return res.status(400).json({ error: 'Invalid UUID' }); }). Prisma: model User { id String @id @default(uuid()) }. Sequelize: { id: { type: DataTypes.UUID, defaultValue: DataTypes.UUIDV4 } }. For MongoDB, ObjectId is typically preferred over UUID, but UUID works with Binary type for cross-database compatibility.

UUID vs other ID formats in Node.js

UUID v4 (36 chars): Universal standard, no coordination needed, but large for URLs and indexes. nanoid (npm install nanoid): Shorter IDs (21 chars default), URL-safe, cryptographically secure. CUID2 (npm install @paralleldrive/cuid2): Collision-resistant, sortable, secure. ULID: UUID-compatible but time-sortable, better for database indexes. For most Node.js APIs and databases, UUID v4 via crypto.randomUUID() is the safest default — universally understood and supported by every database.