Partial password usability sucks

Nowadays, in order to use a service, you must provide a login and password. In Poland, I got acquainted with a partial password instead of a regular password.

A partial password is a mode of password authentication. By asking the user to enter only a few specific characters from their password, rather than the whole password — Wikipedia

Popular banks in Poland require you to provide partial password like in this example.

Partial password example

The idea is good it gives you an extra layer of protection against password theft (link 1, link 2, link 3). But from user perspective implementation of partial password sucks. It implies that everyone must know their password and even can recall a specific symbol. I cannot for sure. What do I suppose to do if my memory fails? It looks like a password manager is right answer. Unfortunately, my password manager KeePass does not support partial password.

The Only Secure Password Is the One You Can’t Remember — Troy Hunt

Given the fact that my password is secure and I cannot remember it, how should I get those 3rd, 9th, 11th symbol?

At the very beginning of my “user experience”, I was copy-pasting the password into notepad and finding requested symbol with the help of keyboard cursor and one, two, three counts :) It is boring and not secure at all, since the password is revealed so anyone with good memory is able to see my screen and steal the password.

Then I came up to the idea to build a utility — Here is the demo of how it works.

How to use

  • If you don’t trust consider to save the page locally and run it from there, for instance file:///c:/Partial%20password%20calculator%20online.html
  • Open & copy-paste your password there.
  • Click on the requested position of password symbol (or use Tab key). Once the symbol is focused it is already in the clipboard.
  • Paste the symbol from clipboard to the site you are about to log in.
  • Repeat again for the next requested position.

Note: For security reason, after 60 seconds your password will be cleared automatically from so it is safe to leave the utility open for a long time.

Hint: In order to find the utility just google partial password calculator.

The utility is open-sourced here I tested in Chrome 72 (Windows, Android), Firefox 65 (Windows, Android), Internet Explorer 11, Edge 44. You are welcome to contribute, review, fix bugs. Report me bugs here.

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