Complex Number to Polar Form

Enter real part a.
Enter imaginary part b.
Math

Complex Number to Polar Form: calculate results from explicit inputs, with a formula and worked example.

Formula

r = √(a²+b²); θ = atan2(b,a); z = r(cos θ+i sin θ)

Example Calculation

Example inputs
  • Real part a: 3
  • Imaginary part b: 4

3+4i has magnitude 5 and argument approximately 53.1301°.

Method references

Frequently asked questions

How do I use this calculator?

Enter real part a, imaginary part b. The result updates automatically. Use Reset to restore the example values.

What method does it use?

r = √(a²+b²); θ = atan2(b,a); z = r(cos θ+i sin θ). Real finite inputs. Numeric results use floating-point arithmetic; this is not a symbolic computer algebra system. Zero has no unique argument.

Why might a rounded result differ?

The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.

Are my inputs saved online?

No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.

Check the assumptions and units before using this result. Read about calculation methods.