About the Rectangular Form Calculator
Convert a complex number from polar form r∠θ to rectangular form a + bi.
Also known as: polar to rectangular, polar to cartesian complex, r cis theta.
How to use this calculator
- Enter magnitude r, angle θ, angle unit.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
a = r·cos θ · b = r·sin θ
Worked example
Using the values pre-filled in the calculator above:
- Magnitude r = 2
- Angle θ = 60
- Angle unit: Degrees
the calculator returns:
- Rectangular form: 1 + 1.73205081i
- Real part a: 1
- Imaginary part b: 1.7320508076