Complex Number Calculator

Arithmetic on complex numbers a + bi.

Result

Result4 + 2i
|z|4.472136
arg(z)26.57°

Complex Number Calculator — FAQs

How do you multiply complex numbers?

(a+bi)(c+di) = (ac − bd) + (ad + bc)i — i² = −1 does the work.

What is i?

√(−1) — the imaginary unit. Complex numbers a+bi let you solve equations like x²+1=0.

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