Nuid.js

A highly performant unique identifier generator for JavaScript.

Installation

Import the library for node/bun:

npm install nuid

For web and deno you can also:

npx jsr add @nats-io/nuid

Basic Usage

Reference the library in your code. If using you can import or require the npm nuid library supports both Common JS and ESM:

const { nuid, Nuid } = require("nuid");
// or
import { next, Nuid } from "nuid";

// `nuid` is a global instance of nuid, you can use it directly
// `Nuid` is the actual class implementing the nuids, so you can also
// `new Nuid()`.

// To generate a bunch of nuids:
let id = nuid.next();
id = nuid.next();
//

// To generate a new prefix:
nuid.reset();
// note that prefixes are automatically rolled whenever all
// the nuids for the specific prefix have been used.
id = nuid.next();

Performance

NUID needs to be very fast to generate and be truly unique, all while being entropy pool friendly. NUID uses 12 bytes of crypto generated data (entropy draining), and 10 bytes of pseudo-random sequential data that increments with a pseudo-random increment.

Total length of a NUID string is 22 bytes of base 36 ascii text, so 36^22 or 17324272922341479351919144385642496 possibilities.

Migration

The 2.x version of the npm module support both CJS and ESM modules, an ESM only version of the module is available via jsr @nats-io/nuid

If you are migrating from the 1.x.x series, note that getGlobalNuid(), next() and reset() and version property have been removed. Instead, access the exported constant nuid and call next() or reset() on it as shown in the examples above. For version information please refer to your installed module's version information.

If you are migrating from the js-nuid module in npm, there should be no changes except to the location of the import in the npm bundle:

import { nuid } from "./node_modules/esm/index.js";

Supported Node Versions

Support policy for Nodejs versions follows Nodejs release support. We will support and build nuid on even Nodejs versions that are current or in maintenance.

License

Unless otherwise noted, the NATS source files are distributed under the Apache Version 2.0 license found in the LICENSE file.