Nano ID Generator

1. Click "Generate" to create a new Nano ID.
2. Adjust the count to generate multiple IDs at once (up to 100).
3. Change the size (1-64) to control the ID length. Default is 21.
4. Customize the alphabet to use different character sets.
5. Click "Copy" to copy the result to your clipboard.

What is Nano ID?

Nano ID is a tiny, secure, URL-friendly unique string identifier generator. It was created as a modern alternative to UUID (Universally Unique Identifier) for situations where shorter, cleaner IDs are preferred. A default 21-character Nano ID uses a 64-character alphabet (A-Za-z0-9_-) and provides approximately 126 bits of entropy, which is comparable to UUID v4. The key advantage of Nano ID is its compact size: 21 characters versus UUID's 36 characters, with no special characters that require URL encoding.

How Nano ID Generation Works

Nano ID generates random identifiers using a cryptographically secure random number generator (crypto.getRandomValues in browsers or crypto.randomBytes in Node.js). Each character is independently selected from the configured alphabet using uniform random distribution. This approach avoids the bias problems that can occur with naive modulo-based random selection. The default alphabet contains 64 characters (letters, digits, underscore, and hyphen), meaning each character contributes 6 bits of entropy. With 21 characters, the total entropy is 126 bits, making collisions practically impossible for any real-world application.

Common Use Cases

• Database primary keys and document IDs in NoSQL databases
• URL shortener codes and shareable link identifiers
• Session tokens and temporary access codes
• File naming for uploads and generated assets
• Correlation IDs for distributed system tracing and logging
• React component keys and unique DOM element identifiers

Nano ID vs UUID: Choosing the Right Format

UUID v4 is the established standard with broad tooling support across languages, databases, and frameworks. It generates 36-character strings in the format xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx with 122 bits of randomness. Nano ID provides similar collision resistance in a shorter, URL-safe format without hyphens. Choose UUID when you need maximum interoperability with existing systems, database native UUID types, or compliance with standards that require UUID format. Choose Nano ID when you want shorter IDs for URLs, file names, or user-facing identifiers where brevity matters. You can also customize Nano ID's alphabet and length to match specific requirements, such as using only lowercase letters for case-insensitive systems.

For generating secure passwords, try the Password Generator. For random strings with custom character sets, use the Random String Generator. For encoding data in QR codes, see the QR Code Generator.