There are some things here, but for more recent work see Bjørn Kjos-Hanssen's main web site.

Press "Complexities" for the autocomplete JavaScript app. Press "Witnesses" for a screensaver.

Start the complexity lookup over HTTP.


  • Fixed minor bug in the screensaver.
  • Complexity witnesses by HTTP now included up to length 23. Check out for example
  • New version (Javascript) goes up to length 19. All info up to that length is in memory at the same time so it is a bit slow.
  • The web app works great in Opera! Not as well in Chrome, and not at all in Firefox.
  • The autocomplete works in the Chrome browser, but not in a good way: to see the complexity of the string 0 you first have to type 000000000 then delete several 0s. The Android app is better!
  • Because I uploaded data to Google's database via HTTP, only up to length 8 was possible, so that is the current length being used.
  • Using JavaScript (JQuery) to get the data from the Google App Engine database asynchronously, thus no info available in View Source.
011000111100000110       9
means that the string 011000111100000110 has complexity 9. An Android version for 0.99 USD is available in the Google Play Store.