Quick start
- Enter the first binary number using only 0 and 1.
- Choose Add, Subtract, Multiply, or Divide.
- Enter the second binary number.
- Press Calculate binary.
- Read the binary answer, decimal answer, and steps.
What binary means
Binary is base 2. Instead of ten possible digits, binary uses only 0 and 1. Each place value is a power of 2, so 1011 means 8 + 0 + 2 + 1, which equals 11 in decimal.
The calculator shows both forms so you can check a base-2 answer against the decimal value you may already know.
Binary arithmetic
Addition, subtraction, and multiplication return a binary answer and the same result in decimal. For example, 1011 + 110 equals 10001, which is 17 in decimal.
Binary division returns a quotient. If the division is not even, the calculator also shows the remainder. For example, 1101 / 10 equals 110 remainder 1.
Converting binary and decimal
Use the conversion panel when you only need to change number systems. Binary to decimal turns a base-2 number such as 101010 into 42. Decimal to binary turns a whole decimal number such as 42 into 101010.
Spaces and underscores are ignored in binary inputs, so grouped values like 1111 0000 are accepted.
Common examples
Examples from the binary calculator
10001
1111
110 remainder 1
Signed numbers
You can type a leading minus sign for simple signed whole-number calculations, such as -101 + 10. This is useful for quick math, but it is not the same as fixed-width two's complement notation.
History, privacy, and copying
Recent binary answers stay visible in the page while you work. The history is kept only in the current browser tab and is not sent to a server.
Copy answer copies the binary result and decimal result so you can paste it into notes, homework, a message, or another document.