🆔 Generate UUID

Is the online UUID generator free?

Completely 100% free! You can generate UUIDs unlimited, create 1 to 100 UUIDs at once. No registration required, no annoying ads.

Is UUID 36 or 32 characters?

36-character UUID is the standard format with hyphens (-), for example: 550e8400-e29b-41d4-a716-446655440000. 32-character UUID is the format without hyphens. Both are valid, but the 36-character format is recommended according to RFC 4122 standard.

Can UUIDs duplicate?

The probability of UUID v4 duplication is extremely low (~1 in 2^122 ≈ 5.3×10^36). In practice, you can create billions of UUIDs without worrying about duplicates. UUID v1 ensures no duplication thanks to the combination of timestamp and MAC address.

How to generate UUID in code?

UUID for JavaScript:

// Use crypto.randomUUID() (modern browsers)
const uuid = crypto.randomUUID();

// Or use uuid library
import { v4 as uuidv4 } from 'uuid';
const uuid = uuidv4();

UUID for Python:

import uuid

# UUID v4 (random)
my_uuid = uuid.uuid4()
print(my_uuid)  # 550e8400-e29b-41d4-a716-446655440000

# UUID v1 (timestamp)
my_uuid_v1 = uuid.uuid1()

Should I use UUID or Auto-increment ID?

UUID is better when: (1) Distributed systems with multiple databases, (2) Need to create ID before inserting into DB, (3) Want to hide record count, (4) Merge data from multiple sources. Auto-increment ID is better when: (1) Simple database, (2) Need to sort by creation order, (3) Save storage space.

Is UUID case-sensitive?

According to RFC 4122 standard, UUID should be written in lowercase, but when comparing they are case-insensitive. For example: 550e8400-... and 550E8400-... are considered the same.

Can you generate UUIDs in bulk?

Yes! This tool supports UUID bulk generator - create up to 100 UUIDs at once. If you need to generate multiple UUID in the thousands or tens of thousands, you should use code (JavaScript, Python) to create faster.