Binary Calculator

Binary Calculator performs the four basic operations on binary numbers and reports the answer in binary, decimal, hexadecimal and octal at once. The working panel shows the same sum in decimal, which is the quickest way to check a hand calculation: if the decimal arithmetic is right and the conversion is right, the binary answer follows.

Division is integer division, giving a quotient and a remainder rather than a binary fraction. That matches how a processor divides and how most programming languages behave for integers, and the exact decimal value is shown beside it so nothing is lost. Subtraction refuses a negative result, because plain unsigned binary cannot represent one -- that needs two's complement and a fixed register width, which is a different question.

Hexadecimal is shown because it is how binary is written down in practice. Each hex digit is exactly four bits, so 10110 becomes 0x16 and the mapping is mechanical. Anyone reading a memory dump, a colour code or a permissions mask is reading hex that stands for binary.

The page shows its working, not just its answer. Where there is a formula it is printed with your own numbers substituted in, so you can check the result rather than take it on trust -- which is the difference between a calculator you can use for something that matters and one you cannot.

Everything runs inside your browser. What you type is never uploaded, never logged and never stored, and the calculator keeps working if your connection drops after the page has loaded.

• Shows result in binary, in decimal, in hexadecimal, in octal and bits used together, so you are not running it twice
• A results table you can read across
• Prints the formula with your own figures substituted in
• Updates as you type, with no button to press and no page reload
• Copy the result in one click
• Free, no sign-up, and it runs entirely in your browser

The binary calculator is used by writers, developers, students, marketers and anyone else who needs the job done once without installing software. Common cases include:

• Checking binary arithmetic homework
• Adding or multiplying bit patterns by hand
• Converting a binary result into hex for code
• Seeing the quotient and remainder of a binary division