# How to! 7) Count to 1,023 on your fingers

Hi,
as promised, weekend post is here! Ok, so I learned this cool thing when I was on seminar in Hamburg. First I thought that someone is pointing middle finger at me for fun (you will see the reason soon) but it was actually counting method. Though you have only 10 fingers you can use them to produce all numbers from zero to 1,023 which is cool.

If you pay close attention and you know something about computers you know that the number 1,023 is very special. It is 1,024 but one smaller (1,024 is actually the special number).

The thing is that 2^10 is 1,024. And in computers you work in binary system with only 0 or 1  ….    on or off and you get the number of combinations that you can arrange binary system if you put 2 to the power of digits you have. On fingers you can not arrange 1,024, you will see why[1]:

### Method

Turn you palms towards you. Since in Europe we write from left we will start with left thumb (palms still towards you). Now make fists.. that is number 0

Rise your thumb, that is 1. (1000000000)
Put only your index finger up, that is 2. (010000000)Put your thumb and index finger up, that is 3. (1100000000)  –> the number of digits shows the number of fingers you have.

So basically if you have number lets say 17. You want to transef it into binary. You will do this by subtracting the highest 2^x power which is equal or less to the number itself.

The 2^x numbers go like this: 1,2,4,8,16,32,64,128,256,512,1024…

In the case of 17 you will subtract 16 which is 5th number in the row. 5th finger on your palm is your left pinkie so you will put it up. Then you are left with 1 which you again subtract by the highest 2^x number which is equal or less and this time it is 1. 1 is first number and left thumb on your hands.

If you want 349 you have to subtract 256 (9th number – right index finger)
You are left with 93-64 (7th number – right ring finger)27-16 (5th number – left pinkie)
9-8 (4th number – left ring finger)
1-1 (1st number – left thumb)

Now train a little bit and impress your friends 😉 The key is to remember the first nine numbers and at what positions they are. Also you can show others just counting one by one. Just do not turn your hands towards them, numbers 4,5,128,640 and other could be dangerous 😀

Dragallur

[1]The reason why you can not count to 1,024 is of course that you are starting with 0 not 1 so your right thumb stands for 2^9 and not 2^10. You can produce another binary digit with your tongue 😉