node package manager


Node.js Authenticator

Two- and Multi- Factor Authenication (2FA / MFA) for node.js

There are a number of apps that various websites use to give you 6-digit codes to increase security when you log in:

There are many Services that Support MFA, including Google, Microsoft, Facebook, and Digital Ocean for starters.

This module uses notp which implements TOTP (RFC 6238) (the Authenticator standard), which is based on HOTP (RFC 4226) to provide codes that are exactly compatible with all other Authenticator apps and services that use them.

Browser & Commandline Authenticator

You may also be interested in


node.js api

npm install authenticator --save

command line

npm install authenticator-cli --global


node.js api

'use strict';
var authenticator = require('authenticator');
var formattedKey = authenticator.generateKey();
// "acqo ua72 d3yf a4e5 uorx ztkh j2xl 3wiz" 
var formattedToken = authenticator.generateToken(formattedKey);
// "957 124" 
authenticator.verifyToken(formattedKey, formattedToken);
// { delta: 0 } 
authenticator.verifyToken(formattedKey, '000 000');
// null 
authenticator.generateTotpUri(formattedKey, "", "ACME Co", 'SHA1', 6, 30);
// otpauth://totp/ 

command line

# see help
authenticator --help
# generate a key and display qr code
authenticator --qr


generateKey()                               // generates a 32-character (160-bit) base32 key 
generateToken(formattedKey)                 // generates a 6-digit (20-bit) decimal time-based token 
verifyToken(formattedKey, formattedToken)   // validates a time-based token within a +/- 30 second (90 seconds) window 
                                            // returns `null` on failure or an object such as `{ delta: 0 }` on success 
                                            // generates an `OTPAUTH://` scheme URI for QR Code generation. 
generateTotpUri(formattedKey, accountName, issuer, algorithm, digits, period)

OTPAuth Scheme

Note that ISSUER is specified twice for backwards / forwards compatibility.

QR Code

See and

Example use with qrcode.js in the browser:

'use strict';
var el = document.querySelector('.js-qrcode-canvas');
var link = "otpauth://totp/{{NAME}}?secret={{KEY}}";
var name = "Your Service";
                                              // remove spaces, hyphens, equals, whatever 
var key = "acqo ua72 d3yf a4e5 uorx ztkh j2xl 3wiz".replace(/\W/g, '').toLowerCase();
var qr = new QRCode(el, {
  text: link.replace(/{{NAME}}/g, name).replace(/{{KEY}}/g, key)


All non-alphanumeric characters are ignored, so you could just as well use hyphens or periods or whatever suites your use case.

These are just as valid:

  • "acqo ua72 d3yf a4e5 - uorx ztkh j2xl 3wiz"
  • "98.24.63"

0, 1, 8, and 9 also not used (so that base32). To further avoid confusion with O, o, L, l, I, B, and g you may wish to display lowercase instead of uppercase.

TODO: should this library replace 0 with o, 1 with l (or I?), 8 with b, 9 with g, and so on?

90-second Window

The window is set to +/- 1, meaning each token is valid for a total of 90 seconds (-30 seconds, +0 seconds, and +30 seconds) to account for time drift (which should be very rare for mobile devices) and humans who are handicapped or otherwise struggle with quick fine motor skills (like my grandma).

Why not SpeakEasy?

It doesn't use native node crypto and there are open security issues which have been left unaddressed.