About Nano ID Generator – Short, URL-Safe Unique IDs
Nano ID is a tiny, secure, URL-friendly way to create unique string identifiers. Each ID is built from a compact 64-character, URL-safe alphabet, so a default 21-character Nano ID is shorter than a UUID while offering a comparable collision resistance — ideal for primary keys, short links, file names, and request IDs.
This free Nano ID generator creates short unique IDs one at a time or in bulk, with a configurable alphabet and size. Randomness comes from your browser's Web Crypto API using unbiased sampling, so every character is equally likely. Everything runs on your device — nothing you generate is sent to a server.
Features
- Generate compact, URL-safe Nano IDs singly or in bulk
- Choose a preset alphabet (URL-safe, alphanumeric, lowercase, or hex)
- Adjustable ID size for shorter IDs or extra collision resistance
- Crypto-strong, unbiased randomness via the Web Crypto API, fully offline
How to use
- Pick an alphabet preset that fits where the IDs will be used.
- Set the ID size and how many IDs you need, then press Generate.
- Copy a single ID, or use Copy all to grab the whole list.
Frequently asked questions
What is a Nano ID?
A Nano ID is a short, URL-safe unique string identifier. It uses a 64-character alphabet (A–Z, a–z, 0–9, plus "_" and "-"), so a 21-character Nano ID packs roughly the same uniqueness as a UUID in fewer characters.
Is Nano ID better than a UUID?
It depends. A default Nano ID is shorter and URL-safe out of the box, which is handy for links and filenames. UUIDs follow a standardized RFC-4122 format and are widely supported by databases. Both rely on cryptographic randomness and are collision-resistant in practice.
How unique are Nano IDs?
A default 21-character Nano ID has about 121 bits of entropy, making collisions astronomically unlikely. A larger size or alphabet increases uniqueness further; a smaller one keeps IDs short at the cost of some collision resistance.
Are these IDs generated securely and privately?
Yes. Randomness comes from crypto.getRandomValues in your browser, sampled without bias, and generation happens entirely on your device. No IDs are ever sent anywhere.
Related tools
Everything runs locally in your browser — your input is never uploaded.