Click Generate to create a Nano ID
Options
221 (default)64
Bulk Generate
Nano ID vs UUID
| Feature | Nano ID | UUID v4 |
|---|---|---|
| Default length | 21 chars | 36 chars |
| Customizable | ✓ Length + alphabet | ✗ Fixed format |
| URL-safe | ✓ Yes | ✗ Hyphens |
| Size (bytes) | 21 bytes | 36 bytes |
| Crypto-secure | ✓ Yes | ✓ Yes |
| npm weekly downloads | ~50M | ~80M |
Frequently Asked Questions
What is Nano ID?
Nano ID is a tiny, secure, URL-friendly unique string ID generator. The default output is 21 characters using an alphabet of A-Za-z0-9_-. It uses crypto.getRandomValues() for security.
How is Nano ID different from UUID?
Nano ID is shorter (21 chars vs 36), URL-safe by default, and customizable. You can change the length and alphabet. UUIDs have a fixed format. Nano ID has a similar collision probability to UUID v4 at its default size.
Is Nano ID secure?
Yes. Nano ID uses the Web Crypto API (crypto.getRandomValues) which provides cryptographically strong random values. It's as secure as UUID v4 for its default 21-character length.
Can I customize the alphabet?
Yes! You can use any custom alphabet — numbers only, hex characters, lowercase only, or any combination. The tool automatically calculates collision probability for your chosen settings.
What's the collision probability?
With the default 21-character alphabet (64 chars), you'd need to generate ~1 billion IDs per second for ~4 million years to have a 1% probability of collision.