Circuits And Components
Series and parallel circuit calculators for voltage dividers, resistor networks, LED series resistors, shunts, reactance, capacitors, RC timing, and voltage-drop checks.
Electrical Formulas
Voltage, current, resistance, power, energy, power factor, and cost calculators for basic electrical math.
Subcategories
Power, Energy And Cost
Power factor, reactive power, kWh use, time-of-use cost, fuel cost, and energy savings calculations.
Voltage, Current And Resistance
Ohm law, watts, amps, volts, resistance, current, voltage, and DC power calculations.
Published Calculators
Maximum Power Transfer Calculator
Evaluates a known Thevenin source against an entered resistive load and separates matched-load power from efficiency and equipment limits.
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Load Factor Calculator
Converts period energy, period hours, and peak demand into average demand, load factor, and peak-to-average ratio while leaving demand windows and tariff rules outside the result.
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4-20 mA Instrumentation Loop Power Calculator
Reduces two-wire 4-20 mA loop supply, burden, wiring, and device data into voltage drop, transmitter margin, allowable resistance, and loop power.
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Inductor Parallel Value Calculator
Combines two or three uncoupled parallel inductors into an ideal equivalent inductance while leaving current sharing and component ratings separate.
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Inductor Series Value Calculator
Combines two or three uncoupled series inductors into an ideal equivalent inductance while leaving coupling, saturation, and rating checks separate.
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Generator Fuel Cost Calculator
Projects generator fuel use, total fuel expense, and hourly operating cost from entered burn rate, runtime, and fuel price.
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Energy Savings Payback Calculator
Estimates simple energy-project payback from annual kWh savings, electricity rate, and project cost, without modeling financing, rebates, or escalation.
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Control Transformer VA Calculator
Compares sealed VA, simultaneous inrush VA, control voltage, and planning margin into a preliminary control-transformer VA basis and secondary-current context.
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Control Panel Heat Load Calculator
Totals control-panel component losses, duty factors, and external heat into watts, BTU/h, and estimated airflow for thermal review.
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Conductance Calculator
Converts resistance to conductance in siemens for reciprocal circuit relationships and parallel-network checks.
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Capacitor Series Value Calculator
Combines two or three ideal series capacitors into equivalent capacitance while leaving voltage sharing, ESR, tolerance, and balancing checks separate.
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Capacitor Parallel Value Calculator
Combines two or three ideal parallel capacitors into equivalent capacitance while keeping ripple current, ESR, tolerance, and ratings separate.
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Admittance Calculator
Resolves complex admittance magnitude and phase from conductance and susceptance values in siemens and degrees.
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AC Circuit Power Calculator
Resolves apparent, real, and reactive power for a single-phase or balanced three-phase AC load from RMS voltage, RMS current, power factor, and phase model.
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Wheatstone Bridge Calculator
Solve the resistance required for an ideal balanced Wheatstone bridge from three known arm values and the selected unknown position.
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RLC Resonance Calculator
Estimates ideal resonant frequency and first-order series-RLC quality metrics from inductance, capacitance, and series resistance.
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RC Time Constant Calculator (tau and 63.2%)
Estimate the ideal first-order RC time constant and exponential target time from resistance, capacitance, transition mode, and target percentage.
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LED Resistor Calculator
Estimates the ideal current-limiting resistor for a series LED string and shows a rounded-up common-value candidate for component review.
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Impedance Calculator
Estimates AC impedance magnitude, phase angle, and power-factor magnitude from resistance and reactance values already matched to the frequency under review.
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Current Divider Calculator
Estimate ideal current division in a fixed-resistance parallel circuit from total current and up to three branch resistance values.
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Capacitor Code Calculator
Decode common three-digit capacitor markings and convert the nominal value between pF, nF, and uF. Confirm the full marking and component rating before applying the result.
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Watts Amps Volts Calculator
Estimate watts, volts, amps, and apparent power from real power, voltage, phase model, and power factor.
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Voltage Divider Calculator
Calculate voltage-divider output, divider current, effective resistance, and resistor power with or without a load resistance.
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Resistor Color Code Calculator
Calculate a four-band resistor color code value, tolerance, and minimum and maximum resistance from the digit, multiplier, and tolerance bands.
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