UUID / GUID Generator
Instantly generate cryptographically secure UUIDs, GUIDs, NanoIDs, and CUIDs. Build single tokens or bulk generate thousands of IDs directly in your browser.
What is a UUID Generator?
A UUID generator is a tool used to create Universally Unique Identifiers (also known as GUIDs in the Microsoft ecosystem). These are 128-bit numbers used to identify information in computer systems. They are practically guaranteed to be unique without requiring a central database to verify them, making them perfect for distributed systems, database primary keys, and session identifiers.
ZeroTools provides a cryptographically secure, offline UUID generator that allows you to instantly spin up single IDs or bulk-generate up to 10,000 IDs at a time. Because everything happens in your browser using standard Web Crypto APIs, the IDs generated here are safe for production systems.
How to use the UUID Generator
- Select a Format: Choose your required ID structure. We support standard random UUID v4, timestamp-based UUID v1, sortable UUID v7, lightweight NanoIDs, and collision-resistant CUID2s.
- Set Quantity: Need more than one? Enter any number up to 10,000 in the quantity box.
- Apply Modifiers: Use the checkboxes to strip hyphens, convert to uppercase, or wrap the IDs in quotes (useful for pasting directly into JSON or arrays).
- Generate & Export: Click "Generate IDs". You can copy individual IDs by hovering over them, use "Copy All" to grab the whole list, or click "Download (.txt)" to save a massive batch to your local drive.
Features of this Tool
- ✓ 100% client-side — your data never leaves the browser.
- ✓ No sign-up or account required.
- ✓ Cryptographically Secure: Utilizes `crypto.randomUUID()` and `crypto.getRandomValues()` to ensure mathematically random generation.
- ✓ Modern Formats: Beyond standard v4, we support UUID v7 (perfect for database indexing), NanoID, and CUID2 natively in JS.
- ✓ Virtual Rendering: Bulk generate thousands of IDs without crashing or freezing your browser tab.
- ✓ Individual click-to-copy icons for precision work.
Frequently Asked Questions
What is the difference between UUID v4 and v7?
UUID v4 is entirely random. UUID v7, however, is a time-ordered format. The first part of a v7 UUID represents the exact millisecond it was generated, followed by random data. This makes v7 highly optimized for database primary keys because they naturally sort chronologically, preventing database fragmentation.
Is NanoID better than UUID?
NanoID is a modern alternative to UUID. It is significantly shorter (21 characters vs 36 characters) and URL-friendly by default, making it excellent for short-links or public-facing IDs. Despite being shorter, it maintains similar collision resistance to UUID v4 by using a larger alphabet (A-Z, a-z, 0-9, _, -).
Can these IDs have collisions (duplicates)?
While theoretically possible, the chance of a collision with UUID v4 or NanoID is astronomically low. You would need to generate 1 billion UUIDs every second for 85 years to reach a 50% probability of a single duplicate. For all practical software applications, they are completely unique.
Are the generated IDs tracked or saved?
Absolutely not. Because ZeroTools has no backend, the IDs are created directly in your browser's RAM and disappear the moment you close the tab. We have no way to log, track, or save the data you generate.