Complex Number Calculator

Add, subtract, multiply and divide complex numbers, then find real and imaginary parts, magnitude, conjugate and polar form.

Calculate with complex numbers in a + bi form

Enter complex numbers in a+bi form to perform arithmetic or inspect a single number.

The calculator separates real and imaginary parts and can return magnitude, conjugate and polar form.

Features

  • Complex addition, subtraction, multiplication and division.
  • Real and imaginary part output.
  • Absolute value or modulus.
  • Complex conjugate.
  • Polar form with argument in radians and degrees.

Example expressions

  • (2+3i) + (1-4i)
  • (2+3i) - (1-4i)
  • (2+3i)(1-4i)
  • (2+3i)/(1-4i)
  • |3+4i|
  • polar form of 1+i

Related formulas

  • (a+bi)(c+di) = (ac−bd) + (ad+bc)i.
  • |a+bi| = √(a²+b²).
  • Conjugate of a+bi is a−bi.
  • Polar form uses r = √(a²+b²) and θ = atan2(b,a).

How to use this calculator

  1. Enter a complex number using i for the imaginary unit.
  2. Choose an arithmetic operation or a single-number property.
  3. Calculate and inspect the separated real and imaginary parts or polar details.

Common input mistakes

  • Use i, not a variable name, for the imaginary unit.
  • Complex division by 0+0i is undefined.
  • Use parentheses when writing a complex number inside a larger expression.

FAQ

How should I enter a complex number?

Use a+bi form, such as 2+3i, -4i or 5.

Can I divide complex numbers?

Yes. The calculator multiplies by the conjugate of the denominator and rejects division by 0+0i.

What is the magnitude of 3+4i?

Its magnitude is √(3²+4²) = 5.

What is polar form?

Polar form represents a complex number by its modulus r and argument θ instead of separate real and imaginary parts.

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