Generate time-based one time passwords in the browser

Demo

This page lets you easily generate a time-based one time password (TOTP) entirely in the web browser in case you ever lose access to your phone.

It uses the excellent otpauth package, downloaded from raw.githubusercontent.com/hectorm/otpauth/master/dist/otpauth.umd.min.js.

Providing parameters in the URL

Private key

You can provide the key in the URL using the URI fragment or a query parameter, for example: https://totp.danhersam.com/#/KEY or https://totp.danhersam.com?key=KEY

Additional parameters

You can also pass the token digits, period and algorithm using a query string in the URL, for example: https://totp.danhersam.com/?digits=6&period=60&algorithm=SHA256&key=KEY

See supported hashing algorithms for the complete list.

Authy support

To use Authy tokens outside of the Authy app, you need to extract the secret key and convert it to base-32. The resulting token can then be used with this tool.

Extract Authy secret key from Chrome App

Install the Authy app in Chrome.
Enter chrome://extensions in the address bar.
Check Developer mode.
Click the main.html link in the Inspect views section of the Authy app.
Navigate to the Console.
Paste the code below in the console and hit Enter.

appManager.getModel().forEach(model => console.log(`${model.name}: ${model.secretSeed}`));

Convert hex keys to base-32

Convert each exported hex key from above using the hex to base-32 converter in this repository.

Authy settings

Use the following settings for native Authy tokens.

Digits: 7 Period: 10

The period shown in the Authy Chrome App is 20 seconds, but it actually uses 10 second intervals and skips every other token.

If your authenticator application only allows 6 or 8 digits (like FreeOTP), choose 8 digits and use the last 7 digits for your code.

Import using QR codes

To make it easier to import Authy entries into another authenticator app, generate QR codes using my QR code generator.

mestoness/totp-generator