Exact DC relationship
Ohm's law and DC power solver
Solve a DC voltage, current, resistance, and power relationship from two known quantities, then check resistor dissipation.
Engine category
Circuits and Passives
Published tools in this category solve distinct design decisions. Each keeps its assumptions, limits, and next decision visible.
Exact resistive relationship
Voltage-divider designer
Calculate loaded and unloaded voltage-divider output, current, output resistance, and resistor power from an input voltage and resistor pair.
Exact first-order relationship
RC time-constant designer
Calculate an RC time constant, capacitor voltage, resistor current, and five-time-constant settling reference for charge or discharge.
Exact resistive relationship
Series and parallel resistor network
Find the equivalent resistance of a two-resistor series or parallel network using stated nominal values.
Exact resistive relationship
Thevenin equivalent
Reduce an ideal voltage divider to its Thevenin voltage, resistance, Norton current, and optional loaded output.
Standardized value series
Preferred resistor value selector
Choose the nearest E12 or E24 resistor value and see the adjacent available nominal values.
Exact DC relationship
Resistor power and voltage rating
Calculate nominal resistor dissipation and a margin-adjusted minimum rating from applied voltage and resistance.
Exact ideal-capacitor relationship
Series and parallel capacitor network
Find two-capacitor series or parallel capacitance, stored energy, and ideal series voltage split.
Standard approximation
Hold-up capacitor designer
Estimate ideal hold-up capacitance for a constant-current load between a starting and minimum voltage.
Exact first-order relationship
Capacitor discharge and bleeder designer
Calculate an ideal bleeder resistance and initial stress for a capacitor to discharge between two voltages in a stated time.
Exact lumped-element relationship
Complex impedance and reactance
Calculate series RLC reactance, complex impedance magnitude, and phase at one stated sinusoidal frequency.
Exact lumped-element relationship
RLC resonance, damping, and Q
Calculate ideal series-RLC resonant frequency, quality factor, bandwidth, and damping ratio.
Exact DC relationship
Low-voltage wire drop and loss
Calculate loop resistance, voltage drop, and copper loss from conductor area, loop length, current, and resistivity.
Exact resistive relationship
Wheatstone bridge output
Calculate ideal Wheatstone-bridge differential output, midpoint voltages, and common-mode voltage.
Exact ideal relationship
Resistor pulse-load screen
Calculate rectangular-pulse resistor energy, peak power, average power, and duty cycle.
Standard approximation
Decoupling transient estimator
Estimate ideal local capacitance for a current step, duration, and allowed capacitive voltage droop.
Exact ideal relationship
Inductor current-ramp estimator
Calculate ideal inductor current change and final current from constant voltage, inductance, time, and initial current.
Exact ideal relationship
Inductor network
Calculate ideal two-inductor series or parallel equivalent inductance for uncoupled components.
Exact sinusoidal relationship
AC power and power factor
Calculate apparent, real, and reactive AC power with power factor from RMS voltage, current, and phase angle.
Exact resistive relationship
Maximum power-transfer calculator
Find matched load resistance, maximum load power, load voltage, and efficiency for an ideal resistive Thevenin source.
Exact resistive relationship
Star-delta conversion
Convert an ideal three-resistor delta network to its equivalent star-arm resistances.