Complex Number Calculator

Add, subtract, multiply or divide two complex numbers entered as separate real and imaginary parts.

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Calculate with two complex numbers without parsing notation

Enter real and imaginary parts for two values, then choose addition, subtraction, multiplication or division. The calculator displays the result in a plus bi form, its magnitude and its conjugate. Separate numeric fields avoid ambiguity around signs and imaginary notation while still supporting the four core arithmetic operations used in algebra, circuits and signal work.

Keep division and precision limits explicit

Division by zero plus zero i is undefined and is rejected. Results use browser floating-point arithmetic, so small rounding artifacts can appear after repeated operations. The page does not simplify radicals, switch to polar form or preserve exact rational components. Use symbolic mathematics or higher-precision software when exact algebraic structure is required.

Frequently asked questions

How should I enter a negative imaginary part?

Type the negative number directly in the imaginary-part field.

Can I divide by zero plus zero i?

No. Complex division requires a nonzero second value.

What is the conjugate?

It keeps the real part and reverses the sign of the imaginary part.