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Security, Crypto & Encoding
UUID/GUID Generator
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Security, Crypto & Encoding/Random UUID (v4)

UUID/GUID Generator

Generate unique UUIDs (Universally Unique Identifiers) and GUIDs online. Supports Version 4 (Random) and Version 1 (Timestamp). Free developer tool.

UUID v4 (Random)UUID v1 (Timestamp)

What is UUID/GUID Generator?

A UUID (Universally Unique Identifier) or GUID (Globally Unique Identifier) is a 128-bit number used to identify information in computer systems. The probability of generating a duplicate UUID is so close to zero that they are effectively unique across the entire universe, without need for a central coordination authority. This tool supports the two most common versions: Version 4 (UUID v4), which is purely random and most widely used; and Version 1 (UUID v1), which is generated using a timestamp and the node's MAC address (simulated here for privacy). UUIDs are the standard for database primary keys, session IDs, and transaction markers in modern distributed systems.

Input Formats

  • Quantity (1-1000)
  • Version (v4 or v1)
  • Hyphens (Include/Exclude)

Output Results

  • List of UUID strings
  • Format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
  • Copy/Download options

Key Features

Universally Unique: Collision probability is effectively zero
Standard Compliant: Strictly follows RFC 4122 specifications
Multiple Versions: Support for v4 (Random) and v1 (Timestamp-based)
Bulk Generation: Generate up to 1000 UUIDs in a single click
Format Options: Toggle hyphens on/off for different database requirements
Privacy: Generated locally using your browser's crypto API
Export Ready: Copy list or download as a text file
Best & Fast: The best fast UUID generator for developers
Shareable LinksShare a list of generated UUIDs. (Limit: 5KB)

Who is this for?

Database Keys

Developers generating UUIDs to use as primary keys in databases like PostgreSQL or MongoDB.

Primary keyForeign keyDatabase schemaPostgreSQL UUIDMongoDB

Session Management

Creating unique session identifiers for tracking user activity in web applications.

Session IDTracking IDCookie valueRequest ID

Testing & Mocking

QA engineers generating bulk UUIDs to populate test databases or mock API responses.

Test dataMock APISeed dataQA tools

How to Use

1

Select the UUID Version (v4 is recommended for most use cases).

2

Enter the quantity you need (e.g., 5).

3

Click 'Generate'.

4

Copy the list or download as a text file.

Examples

Input

Generate 1 UUID v4

Output

f47ac10b-58cc-4372-a567-0e02b2c3d479

Common Errors

  • Assuming v1 is random (it contains time/mac info)
  • Using UUIDs for security tokens (they are predictable)
  • Storing as string instead of binary (inefficient in DB)

Code Examples

JavaScript (Web Crypto)

const uuid = crypto.randomUUID();
console.log(uuid);

Python

import uuid
print(uuid.uuid4())

Frequently Asked Questions

What is the difference between v1 and v4?
v4 is completely random and most popular. v1 includes the current time and your computer's ID. Use v4 unless you specifically need time-based sorting.
Can UUIDs collide?
It's mathematically possible but practically impossible. You'd have to generate billions of UUIDs per second for years to even have a tiny chance of a duplicate.
Are UUIDs case sensitive?
No, they are hexadecimal numbers, so case doesn't matter. However, lowercase is the standard convention and what I generate by default.
Can I use UUIDs as passwords?
No! UUIDs are unique, but they are not secure passwords. They are predictable (especially v1) and shouldn't be used for secrets.