🔑 UUID / GUID Generator

About UUID / GUID Generator

A UUID (Universally Unique Identifier) is a 128-bit identifier widely used in software development, databases, APIs, and distributed systems. GUID (Globally Unique Identifier) is essentially the same — the term used in Microsoft technologies. This tool generates UUIDs locally in your browser using the Web Crypto API. No data is sent to any server.

How to Use

1. Select a UUID version — v4 (random) for general use, v7 (time-ordered) for database keys.
2. Set the quantity (1–1000) and choose format options in the sidebar.
3. Click "Generate UUID" — results appear instantly.
4. Click "Copy All" or click a single line to copy individually.

Frequently Asked Questions

What is the difference between UUID v4 and v7?

UUID v4 is entirely random (122 random bits), best for unpredictable general-purpose IDs. UUID v7 combines a 48-bit millisecond Unix timestamp with random data, producing time-sorted IDs ideal for database primary keys with better index performance.

Are UUIDs guaranteed to be unique?

Not mathematically, but collisions are extremely unlikely. UUID v4 has ~5.3×10³⁶ possible values, making duplicates virtually impossible in practice.

Will bulk-generated UUIDs have duplicates?

This tool uses crypto.getRandomValues(), a cryptographically secure RNG. Even 1,000 UUIDs at once have negligible collision probability.

Can I use UUIDs as database primary keys?

Yes. UUIDs are widely used as DB primary keys. UUID v7 is recommended for its time-ordered nature, improving index insert performance. PostgreSQL, MySQL, and SQL Server natively support UUID types.

Are the generated UUIDs secure?

All UUIDs are generated locally in your browser using the Web Crypto API. No data is sent to any server.