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🚀 Getting StartedBasic Usage

Last Updated: 3/12/2026

Basic Usage

Nanoid provides a simple API for generating unique IDs. By default, it generates 21-character URL-safe IDs using a secure random generator.

Generate an ID

import { nanoid } from 'nanoid'
 
const id = nanoid()
console.log(id) //=> "V1StGXR8_Z5jdHi6B-myT"

The default 21-character ID provides collision probability similar to UUID v4.

Custom ID Size

Pass a size argument to generate shorter or longer IDs:

nanoid(10) //=> "IRFa-VaY2b"

Important: Smaller IDs increase collision probability. Use the ID collision calculator  to verify your ID size is safe for your use case.

Default Alphabet

Nanoid uses URL-friendly characters by default: A-Za-z0-9_- (64 characters total).

This alphabet is optimized for:

  • URL safety (no encoding needed)
  • Readability (avoids ambiguous characters)
  • Compression efficiency (character order optimized for gzip/brotli)

Blocking Behavior

The default nanoid() function is synchronous and may briefly block the CPU while collecting entropy from the hardware random generator. For most applications, this is negligible.

If you need non-blocking ID generation or don’t require cryptographic security, see the Non-Secure guide.

Common Use Cases

Database primary keys:

const user = {
  id: nanoid(),
  name: 'Alice'
}

File names:

const filename = `upload-${nanoid()}.jpg`

API tokens (use longer IDs for security):

const token = nanoid(32)

What’s Next

InstallationCustom Alphabet Size