Binary Addition Calculator

Perform binary addition with unlimited-length values, inspect every carry, and verify the answer in binary, decimal, and hexadecimal.

Enter two binary numbers

Use 0 and 1 only. Spaces, underscores, leading zeros, and an optional minus sign are supported.

Addition result

Binary

1001000
Decimal check
72
Hexadecimal check
48

Carry steps

101101 + 11011 = 1001000

  1. 1.1 + 1 + 0 = 0 | ↖ 1
  2. 2.0 + 1 + 1 = 0 | ↖ 1
  3. 3.1 + 0 + 1 = 0 | ↖ 1
  4. 4.1 + 1 + 1 = 1 | ↖ 1
  5. 5.0 + 1 + 1 = 0 | ↖ 1
  6. 6.1 + 0 + 1 = 0 | ↖ 1
  7. 7.1 → MSB

What is binary addition?

Binary addition combines base-2 numbers by adding one column at a time from right to left. Because each position can contain only 0 or 1, a column total of two is written as 0 with a carry of 1. This binary addition calculator applies the same rule without limiting the length of the numbers. It validates the input, preserves exact integer precision, and returns a result that can be checked in three number systems.

The four binary addition facts are simple: 0 + 0 = 0, 0 + 1 = 1, 1 + 0 = 1, and 1 + 1 = 10. A carry from the previous column can make 1 + 1 + 1 = 11. Learning those facts makes addition in the binary system as predictable as decimal addition. The difference is that a carry starts at two instead of ten.

How to use this binary addition calculator

Type the first value and the second value into the fields, then select Add binary numbers or press Enter. The binary addition calculator accepts spaces and underscores as visual separators, so values such as 1010 1100 and 1010_1100 are valid. It also accepts a leading minus sign for signed arithmetic. Invalid digits are rejected before any calculation is displayed.

After binary addition runs, the main answer appears in base 2. Decimal and hexadecimal checks appear beside it, which makes the result useful for programming, digital logic, and coursework. Use the copy button to move the exact binary answer into another application. Swap reverses the operands, while Clear removes both inputs and the previous result.

Reading carry steps in binary addition

For non-negative inputs, the binary addition calculator lists each column beginning with the least significant bit. A step such as 1 + 1 + 0 = 0, carry 1 means the current column writes 0 and sends 1 to the next column. If the last column still has a carry, that carry becomes a new leading bit. These steps let you audit the answer instead of treating the calculator as a black box.

Consider 1011 + 0110. From the right, 1 + 0 gives 1. Next, 1 + 1 gives 0 with carry 1. The following column is 0 + 1 + 1, which again gives 0 with carry 1. The final column gives 1 + 0 + 1 = 10, so binary addition produces 10001. In decimal, this confirms 11 + 6 = 17.

Why exact binary addition matters

JavaScript number values lose integer precision beyond a fixed range, but this binary addition calculator uses arbitrary-precision integer arithmetic. Long register masks, identifiers, test vectors, and classroom examples therefore remain exact. Your values are processed locally in the browser and are not uploaded to a calculation service.

Binary addition appears in arithmetic logic units, address offsets, checksums, counters, and bit-level algorithms. A binary number calculator is useful when you need a fast answer, while the visible carry trail teaches the method. The decimal check helps catch a copied digit, and the hexadecimal form gives programmers a compact representation of the same result.

Signed values, leading zeros, and formatting

A leading minus sign represents a negative integer, so -101 + 11 equals -10 in binary and -2 in decimal. Signed binary addition can depend on a fixed width when hardware uses two's complement; this page instead performs mathematical signed-integer addition without assuming a bit width. That choice prevents silent overflow and keeps the meaning of the input explicit.

Leading zeros do not change a mathematical value. The binary addition calculator normalizes them in the calculated equation, while separators are removed before evaluation. If a protocol requires fixed-width output, copy the result and pad it to the required register or field width after confirming that it fits.

Practice binary addition effectively

Start with four-bit examples, predict the carries on paper, and then compare your work with the steps. Next, try inputs with consecutive 1 digits, because they create carry chains. Finally, test unequal lengths and negative values. This sequence turns the binary addition calculator into a learning aid instead of only an answer generator.

For related work, use the binary-to-decimal converter to inspect place values and the binary-to-hex converter to group bits into nibbles. The dedicated binary subtraction page explains borrowing. Keeping each operation on its own page preserves a clear search intent while the wider binary math calculator cluster provides natural routes between tasks.

Binary addition examples

Use these verified sums to practice binary digit addition and compare the base-2 answer with its decimal value.

FirstSecondBinary sumDecimal equation
0000 + 0 = 0
11101 + 1 = 2
10111101000111 + 6 = 17
111111000015 + 1 = 16
-10111-10-5 + 3 = -2

Binary addition FAQ