16 base calculator online free：It is very simple to remember the decimal numbers represented by the letters in the hexadecimal system. Remember A(10), B(11), C(12), D(13), E(14), F(15). However, due to inertial thinking, sometimes we often make the mistake of misreading the decimal numbers represented by letters by one digit more, such as misreading A as 11 and B as 12. Therefore, we must remember that A is 10, not 11, and the values represented by other letters should also be noted. Hexadecimal addition and subtraction are the same as decimal addition and subtraction algorithms. Just remember a few key points. Take 6AE9H+4B7CH for example. The first digit is 9+C(12)=21. If the result is ≥16, then subtract 16 from the result and then carry the previous digit over, so the result is 5. E(14)+7=21, carry the previous digit over, so the result is 22. Subtract 16 to get 6, then carry the previous digit over. A(10)+B(11)=21, carry the previous digit over, so the result is 22. Subtract 16 to get 6, then carry the previous digit over. 6+4=A(10), carry the previous digit over, so the result is B(11). So 6AE9H+4B7CH=A665H.
The same principle applies to subtraction of hexadecimal numbers, but note that when the number is not enough to subtract, the value borrowed from the previous number is not 10, but 16. For example, if 4-9 is not enough to subtract, the value borrowed from the previous number is not 14-9, but 20-9.