Electrical
Electrical Calculator
Calculate Ohm's law, power, resistor/capacitor/inductor series and parallel values, capacitive reactance, inductive reactance, resonance frequency, and RC/RL time constants with SI unit conversion.
Ohm's law / Power
Enter any two values to calculate voltage, current, resistance, and power.
Series / Parallel equivalent
Capacitive / Inductive reactance
LC resonance frequency
RC / RL time constant
Formulas
Ohm's law and power
V = I × R；I = V / R；R = V / I；P = V × I = I² × R = V² / R
Series / Parallel
Rseries = ΣR；1/Rparallel = Σ(1/R)。Cseries = 1 / Σ(1/C)；Cparallel = ΣC。Lseries = ΣL；1/Lparallel = Σ(1/L)。
Reactance
Xc = 1 / (2πfC)；XL = 2πfL。f 使用 Hz，C 使用 F，L 使用 H，结果为 Ω。
Resonance
f0 = 1 / (2π√(LC))。L 使用 H，C 使用 F，结果为 Hz。
Time constant
τRC = R × C；τRL = L / R。结果为秒 s，约 5τ 可视为接近稳态。
Precision notes
Calculations convert to SI base units first and display up to 4 decimal places. Inputs must be finite positive numbers; parallel calculations reject zero or negative values. Real circuits should also account for tolerance, temperature drift, ESR, parasitics, and power ratings.