This website allows you to generate a TOTP (Google Authenticator) Token,
it runs completely in your browser and can be used offline.
This site is currently online.
We recommend that you run it offline if you are going to use it for real codes.
You can download an offline copy.
If the link does not prompt for a download,
you can right click it and then save the link target as totp.html
(or any other file name).
When you enable two factor authentication with Google authenticator for a service,
write down the secret that is displayed next to the QR code.
You can enter the secret on this page if you need the code.
Codes are only valid for 30 seconds but most servers accept them a few minutes longer,
so ensure that your clock is set accurately.
Most websites will give you a Base32 code and ask for 6 digits,
which means you can leave these two fields as-is.
Your input is stored in the URL when you generate a token.
This means you can set a bookmark to that specific URL to have the fields pre-filled.
This allows you to store tokens in form of bookmarks.
Securely using TOTP
Do not blindly enable Two factor authentication using Google Authenticator.
Be sure you can get access in case you lose your device.
If you can, register the same token on multiple devices.
Don't rely on the backup/sync of the device.
You can store the secret code and settings in a password manager.
The idea of Two Factor authentication is that you need to posess a device with the secret on it.
To not subvert this principle,
use a different computer to store the password file.
When enabling Two Factor Authentication,
be sure the website gives you a way to log in if you lose the device.
You can often enable multiple Two factor logins at once.
As long as you are able to proceed with one of them you should get in.