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UUID Generator

Generate random UUID v4 identifiers instantly. Free, no signup, 100% local.

v4 UUID Batch Copy  1-click

Generated

Click "Generate UUIDs" to create identifiers.

How it works

Three simple steps —everything happens in your browser.

1

Set your options

Choose how many UUIDs you need, and whether to use uppercase and hyphens.

2

Generate

Click Generate. Each UUID uses the cryptographic random API for a unique v4 identifier.

3

Copy & use

Click Copy to copy all generated UUIDs to your clipboard for use in code or data.

Why use Ercc UUID Generator?

Truly random v4

Uses crypto.getRandomValues for cryptographically strong randomness, not a predictable algorithm.

Batch generation

Generate up to 50 UUIDs at once —ideal for seeding test data, migrations, or mock records.

100% private

Everything runs locally. Your generated identifiers never leave your device.

What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information in computer systems. Also called a GUID, a v4 UUID is generated from random numbers, making collisions astronomically unlikely.

UUIDs are widely used for database primary keys, distributed systems, API identifiers, session tokens, and test data. They let separate systems generate identifiers without needing a central coordinator.

How to generate a UUID for free

Generating UUIDs with Ercc is instant and free:

  1. 1. Set the quantity, case, and whether to include hyphens.
  2. 2. Click Generate UUIDs.
  3. 3. Copy the list and paste it into your code, database, or document.

There is no limit and no watermark. All generation happens locally in your browser.

FAQ

Frequently Asked Questions

What is the difference between UUID v1 and v4?

UUID v1 is generated from a timestamp and the machine's MAC address, so it reveals when and where it was created. UUID v4 is essentially random, providing better privacy.

Can two generated UUIDs ever be the same?

Technically yes, but the probability is astronomically small. A v4 UUID has 122 random bits, so collisions are negligible.

Should I use uppercase or lowercase UUIDs?

Both are valid. Lowercase is the most common convention in code and databases. Uppercase is sometimes preferred for display or print.

Do I need hyphens in a UUID?

Hyphens are the standard formatting (8-4-4-4-12) used by most systems. Removing them gives a compact 32-character string for URLs or filenames.

Is the UUID generator really free?

Yes, 100% free with no limits and no watermark. Everything runs locally in your browser.