Nano ID Generator

What is a Nano ID?

A Nano ID is a short random ID, 21 characters by default, made only of characters that are safe to use in URLs.

Nano ID is a small open-source library, not a formal standard. By default it picks 21 characters from a 64-character alphabet: A to Z, a to z, 0 to 9, underscore and hyphen. Each character carries 6 random bits, so a default ID has 126 bits of randomness, a little more than the 122 in a UUID v4.

It packs that into 21 characters instead of 36, and needs no encoding in links. You can pick a shorter length or a different alphabet, but every change to either one changes how likely a repeat is.

What a Nano ID looks like

Here is the ID you just made. ClickTap Generate above and watch it change.

• Every character is random. There is no version digit, no time and no fixed layout. With the default alphabet, each one adds 6 bits.

When to use Nano ID

How short can a Nano ID be?

Shorter IDs are easier to read, but they repeat sooner. These figures use the default URL-safe alphabet. Check your length against how many IDs you will ever make.

Make a Nano ID in code

import { nanoid } from 'nanoid';

const id = nanoid();     // 21 characters
const short = nanoid(10); // 10 characters
console.log(id, short);

import { customAlphabet } from 'nanoid';

const hexId = customAlphabet('0123456789abcdef', 12);
console.log(hexId()); // like 4f90d13a42bc

from nanoid import generate

id = generate()                          # 21 characters
hex_id = generate('0123456789abcdef', 12)  # alphabet, then length
print(id, hex_id)

import gonanoid "github.com/matoous/go-nanoid/v2"

id, err := gonanoid.New()
if err != nil {
	log.Fatal(err)
}
fmt.Println(id)

use nanoid::nanoid;

let id = nanoid!();
let short = nanoid!(10);
println!("{id} {short}");

Nano ID vs UUID v4, ULID and UUID v7

Questions people ask