How to Generate UUIDs in JavaScript, Python, and Go

What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit identifier that's practically guaranteed to be unique. The most common version, UUID v4, uses random numbers.

Format: 550e8400-e29b-41d4-a716-446655440000

JavaScript

Modern browsers and Node.js support crypto.randomUUID():

const uuid = crypto.randomUUID();
console.log(uuid);
// "550e8400-e29b-41d4-a716-446655440000"

No dependencies needed! This is available in all modern browsers and Node.js 16+.

Python

Python has a built-in uuid module:

import uuid

new_uuid = uuid.uuid4()
print(new_uuid)
# 550e8400-e29b-41d4-a716-446655440000

Go

Go's google/uuid package is the standard choice:

package main

import (
    "fmt"
    "github.com/google/uuid"
)

func main() {
    id := uuid.New()
    fmt.Println(id.String())
}

Quick Generator

Don't want to write code? Use our UUID Generator to create UUIDs instantly. Supports bulk generation, uppercase, and no-dashes format.

When to Use UUIDs

• Database primary keys — avoid sequential IDs that expose record counts
• API request IDs — trace requests across microservices
• File names — prevent collisions in upload systems
• Session tokens — unique identifiers for user sessions

UUID v4 vs Others

| Version | Source | Use Case | |---------|--------|----------| | v1 | Timestamp + MAC | Time-ordered, but exposes hardware info | | v4 | Random | Most common, no information leakage | | v5 | Namespace + SHA-1 | Deterministic from input | | v7 | Timestamp + Random | New! Time-ordered like v1 but random |

For most use cases, v4 is the best choice — it's simple, random, and widely supported.