How to convert decimal to binary by hand?

You have to divide decimal number by 2 and then to write the reminder. Then you have to continue to divide the result by 2 and so on. At the end you have to read all those reminders (numbers 0 and 1) backwards and you will get the binary number. Example: Convert 10 (decimal) to binary.

10 : 2 = 5 | 0

5 : 2 = 2 | 1

2 : 2 = 1 | 0

1 : 2 = 0 | 1

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Finally: 10 (decimal) = 1010 (binary)