Why The Number Pad On Calculators And Mobile Phones Are Reversed ? ?

I am a student. Fortunately from today’s generation, where we do have gadgets like calculator and mobile phones so as to help us study ( Quite a contradiction statement, I know ! ! ). The reason for my optimistic approach towards such electronic gadgets is because they help us reduce our work time by doing fast calculations and good google search.
Now it will quite a bit foolish of me to ask you people that whether you have ever used a calculator and a mobile phone. Of course, we all did. But have you ever noticed any difference, well apart from calculator being an in built feature in most of the smart phones ! !
This is my phone’s dialer keypad.
And if you can take an effort to just put your ‘arse’ up and walk up to your study table, you can again spot the difference between your Landline’s Dialer Keypad and scientific calculator’s keypad.
Ever wondered about why is the number pad in a reversed position ? Any idea ?
  • The first theory deals with the telephone’s keypad circuit and tone-recognition hardware. When the touch-tone telephones were gaining its popularity in the late 1950s, the calculator and adding-machine designers had already decided a layout that had 7, 8 and 9 at the top row. Data-entry professionals, and others who used calculators quite regularly, were able to master at navigating the keypads.
They could hit the numbers extremely quickly and efficiently, which was great for data entry, but not so great for dialing a touch-tone telephone. The tone-recognition technology could not operate as effectively at the speeds at which these specialists dialed the numbers.

  • The telephone designers figured out that if they reverse the layout, the dialing speeds for these specialists would decrease and the tone-recognition would be able to do its job more reliably. Although this theory is still not considered as a relevant source for the reason, but it does make sense.
  • The real reason which I feel, lies in the study conducted by Bell Labs titled “Human Factor Engineering Studies of the Design and Use of Pushbutton Telephone Sets.” which was published in the July 1960 which states that the researchers tried various number of different layouts including the 5X2 matrix arrayed either horizontally or vertically, also a 3X3 matrix with the ‘zero’ at the bottom. The study showed that that the 3X3 version with 1-2-3 in the top row was the easiest for people to master and the rest you know is history.
  • Now there can be another reason for such a reverse swapping. When it came time to match letters of the alphabet up on the number buttons, writing down 1-2-3 at the top made a lot more sense because it was the most natural way to get A-B-C in the top row.

  • If 7-8-9 had been across the top, one of two things would have happened, the letters and the numbers would have gone in opposite directions, or P-R-S would have been the first set of letters which in either way would have been quite odd ! !
Now there can be many more reasons, if you have any relevant one, please feel comfortable and share it with us ! !


Please enter your comment!
Please enter your name here