Techniques for preventing typographical errors on digital soft keyboards are implemented by a computing device with a touch-screen display. According to one technique, a plurality of soft keys of a soft keyboard is displayed on the touch-screen display. Each soft key covers an area of the touch-screen display. One or more occurrences of a particular typographical error in which a user erroneously selects an adjacent soft key in addition to or instead of an intended soft key are detected. In response, an activation region of the intended soft key is changed to decrease the probability of the user making the same typographical error in the future.