Binary Calculator

Add, subtract, multiply, and divide binary numbers.

Binary calculator

Add two binary numbers.

Use conversion mode to switch between binary, decimal, and hexadecimal.

Leading zeros may be useful for fixed-width values.

Bitwise operations compare bits position by position.

Binary result

1101

Binary addition

Decimal equivalent

13

Same value in base 10.

Hexadecimal equivalent

D

Same value in base 16.

Binary result

1101

Grouped by four bits for readability.

Bit length

4

Number of bits needed to display the unsigned magnitude.

Remainder

-

Only shown for division when applicable.

Binary numbers use only 0 and 1. Results are shown in binary, decimal, and hexadecimal so students and developers can cross-check quickly.
Updated May 2026Formula verifiedRuns in your browser
Binary arithmetic follows the same idea as decimal arithmetic, but every place carries in base 2.
Leading zeros do not change an unsigned value, but they matter for fixed-width displays.
Binary addition carries after 1 + 1 because 10₂ is the next value after 1₂.

Step-by-step interpretation

1

Convert 1010₂ to 10₁₀.

2

Convert 11₂ to 3₁₀.

3

10 + 3 = 13.

4

Convert the result back to binary: 1101₂.

Number system

Binary number system explanation

Base 2

Binary is base 2, so each digit can only be 0 or 1.

Bits

Binary digits are called bits, short for binary digits.

Powers of 2

Each place value is a power of 2, starting at 2^0 on the right.

Computers

Computers use binary because bits map naturally to off and on states.

1011₂ = 8 + 0 + 2 + 1 = 11₁₀

Arithmetic

Binary arithmetic operations

Addition

Binary addition carries when 1 + 1 = 10₂.

Subtraction

Binary subtraction may borrow from the next place value.

Multiplication

Binary multiplication works like decimal multiplication, but only 0 and 1 appear.

Division

Binary division follows long division ideas and may leave a remainder.

Conversion

Binary to decimal conversion

To convert binary to decimal, multiply each bit by its place value and add the results.

Binary1101
Place value8421
Contribution8401

1101₂ = 1x8 + 1x4 + 0x2 + 1x1 = 13₁₀

Conversion

Decimal to binary conversion

Divide by 2

Repeatedly divide by 2 and track each remainder.

13 / 2 = 6 remainder 1

6 / 2 = 3 remainder 0

3 / 2 = 1 remainder 1

1 / 2 = 0 remainder 1

13₁₀ = 1101₂

Developer basics

Bitwise operations basics

Truth table

ABANDORXOR
00000
01011
10011
11110

AND

1 only when both bits are 1.

OR

1 when at least one bit is 1.

XOR

1 when bits are different.

Shifts

Move bits left or right by a chosen amount.

Examples

Worked examples

1010 + 11

Add with base-2 carries

1010 + 0011 = 1101

13₁₀

1101 - 101

Subtract after aligning bits

1101 - 0101 = 1000

8₁₀

101 x 11

Multiply by each 1 bit

101 x 11 = 1111

15₁₀

1101₂ to decimal

Add powers of 2

8 + 4 + 0 + 1

13₁₀

25₁₀ to binary

Divide by 2

remainders 1,0,0,1,1

11001₂

1010 AND 1100

1 only where both bits are 1

1010 AND 1100

1000₂

1010 OR 1100

1 where either bit is 1

1010 OR 1100

1110₂

101 << 1

Move bits left once

101 becomes 1010

10₁₀

Avoid errors

Common mistakes

Entering digits other than 0 and 1 in binary mode.
Forgetting binary is base 2, not base 10.
Reading place values from the wrong direction.
Ignoring carries in binary addition.
Confusing XOR with OR.
Forgetting leading zeros matter in fixed-width binary.
Mixing signed and unsigned interpretations.
Assuming left shift always multiplies by 2 in every context.

Rules

Formula and rule explanation

Binary place value

Value = sum of each bit multiplied by 2 raised to its position.

Binary to decimal

Decimal = b_n x 2^n + b_(n-1) x 2^(n-1) + ... + b_0.

Decimal to binary

Repeatedly divide by 2 and read remainders from last to first.

Addition rules

0 + 0 = 0, 0 + 1 = 1, 1 + 0 = 1, 1 + 1 = 10₂.

Bitwise AND

1 only when both bits are 1.

Bitwise OR and XOR

OR is 1 when at least one bit is 1. XOR is 1 when bits are different.

FAQ

Binary calculator questions

A binary number is a base 2 number that uses only 0 and 1. Each digit is a bit, and each place value represents a power of 2.