Electrical Calculators
9 free electrical calculators in the Engineering & Electrical category. Each tool gives instant results and explains the formula so you can follow the calculation.
Cable Size Calculator
Pick the smallest copper cross-section keeping voltage drop within about 3% (simplified)
Open calculator โCurrent Calculator
V = I x R; P = V x I (leave the unknown as 0)
Open calculator โOhm's Law Calculator
V = I x R; P = V x I (leave the unknown as 0)
Open calculator โParallel Resistor Calculator
Series: R = sum. Parallel: 1/R = sum(1/Ri)
Open calculator โResistor Calculator
Series: R = sum. Parallel: 1/R = sum(1/Ri)
Open calculator โVoltage Divider Calculator
Vout = Vin x R2 / (R1 + R2)
Open calculator โVoltage Drop Calculator
Vdrop = 2 x I x (resistivity x length / area)
Open calculator โWatts to Amps Calculator
I = P / (V x pf)
Open calculator โkVA to Amps Calculator
3ph: I = kVA x 1000 / (sqrt(3) x V); 1ph: I = kVA x 1000 / V
Open calculator โAbout electrical calculations
This page groups the electrical tools within Engineering & Electrical. Pick a calculator above to enter your values and get an instant result, complete with the formula, a step-by-step breakdown and a worked example. All calculators are mobile-friendly, accessible and free.
What are electrical calculators used for?
These tools help you with electrical calculations in the engineering & electrical category, giving instant results with the formula and a worked example on each page.
Are they free and private?
Yes. They are free, require no sign-up, and run entirely in your browser so your inputs stay on your device.