⌘K
We use cookies to improve your experience
We use essential cookies to make our site work. With your consent, we may also use non-essential cookies to improve user experience.
Battery series/parallel, voltage divider, transformer, motor power, and electrical calculators.
Calculate total voltage and capacity for batteries in series and parallel.
Calculate output voltage from R1, R2, and input voltage.
Calculate total inductance for inductors in series and parallel.
Calculate RC time constant and charging curve from resistance and capacitance.
Calculate secondary voltage and turns ratio from primary voltage and turns.
Calculate motor power in watts and HP from torque and RPM.
Look up maximum amperage for wire gauges by insulation type. NEC reference.
Calculate battery bank size in Ah from daily usage, autonomy days, and depth of discharge.
Calculate minimum inverter wattage from a list of appliances with safety margin.
Calculate total electrical load from circuits and check panel capacity.
Convert watt-hours to kilowatt-hours.
Convert kilowatt-hours to watt-hours.
Calculate inverting and non-inverting op-amp gain from resistor values.
Calculate RC low-pass or high-pass filter cutoff frequency.
Calculate minimum PCB trace width for a given current.
Convert between power and voltage ratios in decibels.
Calculate antenna length for a given frequency.
Calculate air-core coil inductance from turns, diameter, and length.
Calculate MOSFET power loss from Rds(on) and current.
Calculate ADC step size and resolution from bits and reference voltage.
Calculate PWM duty cycle from on-time and period.
Calculate relay coil current from voltage and resistance.
Convert milliamperes to amperes.
Convert amperes to milliamperes.
Convert circular mils to square millimeters for wire gauge area.
Convert square millimeters to circular mils for wire sizing.
Convert between farads, microfarads, nanofarads, and picofarads.
Convert between henrys, millihenrys, and microhenrys.
Convert between webers, maxwells, and volt-seconds.
Convert between teslas, gauss, and oersteds.
Convert between coulombs, ampere-hours, and milliampere-hours.
Convert between amperes, milliamperes, and microamperes.
Convert between volts, millivolts, and kilovolts.
Convert between ohms, kilohms, and megohms.
Convert between siemens, millisiemens, and microsiemens.
Calculate power factor from real and apparent power values.
Calculate reactive power in VAR from voltage, current, and phase angle.
Calculate apparent power in VA from voltage and current.
Calculate three-phase power from line voltage, current, and power factor.
Calculate single-phase power from voltage, current, and power factor.
Calculate transformer turns ratio from primary and secondary voltages.
Calculate transformer efficiency from input and output power.
Calculate electric motor efficiency from shaft and input power.
Calculate generator output power from RPM, torque, and efficiency.
Estimate solar panel energy output from wattage, sunlight hours, and efficiency.
Estimate wind turbine power output from rotor diameter and wind speed.
Calculate annual savings from switching to smart LED bulbs.
Compare LED and incandescent bulbs on cost, lifespan, and energy use.
Calculate number of light fixtures needed for target lux by room size.
Calculate total lumens needed for a room based on area and usage type.
Calculate optimal motion sensor placement by room layout and coverage angle.
Estimate annual savings from programmable thermostat setback schedules.
Calculate energy usage and cost for devices controlled by smart plugs.
Calculate number of solar panels needed to offset your electricity bill.
Calculate battery bank capacity for off-grid or backup power systems.
Calculate UPS battery runtime from VA rating and connected load.
Calculate ethernet cable length needed between rooms including wall routes.
Estimate WiFi coverage area from router specs and building materials.
Find optimal router placement based on floor plan and device locations.
Calculate number of mesh WiFi nodes needed by floor area and layout.
Calculate number of security cameras needed by property perimeter and angles.
Calculate optimal doorbell and video doorbell mounting height.
Calculate smoke detectors needed by rooms and code requirements.
Calculate carbon monoxide detector placement by floor and fuel sources.
Identify optimal water leak sensor locations by appliance and pipe layout.
Compare smart lock features by connectivity, battery life, and compatibility.
Calculate conduit fill percentage from wire count and conduit size.
Convert microwatts to milliwatts for low-power electronics.
Convert milliwatts to microwatts.
Convert nanowatts to microwatts for sensor applications.
Convert microwatts to nanowatts.
Convert picowatts to nanowatts for RF measurements.
Convert megavolts to kilovolts for high-voltage engineering.
Convert kilovolts to megavolts.
Convert gigavolts to megavolts.
Convert microfarads to picofarads for capacitor selection.
Convert picofarads to microfarads.
Convert nanofarads to picofarads.
Convert picofarads to nanofarads.
Convert millihenrys to microhenrys for inductor values.
Convert microhenrys to nanohenrys for RF inductors.
Convert nanohenrys to picohenrys for microwave circuits.
Convert webers to maxwells for magnetic flux.
Convert maxwells to webers.
Convert tesla to gauss for magnetic field strength.
Convert gauss to tesla.
Convert coulombs to ampere-hours for battery capacity.
Convert ampere-hours to coulombs.
Convert farads to microfarads for capacitance values.
Convert microfarads to farads.
Convert siemens to mhos for electrical conductance.
Convert mhos to siemens.
Convert lumens to candela given beam angle.
Convert candela to lumens given beam angle.
Convert lux to foot-candles for lighting design.
Convert foot-candles to lux.
Convert phots to lux for illuminance.
Convert lux to phots.
Convert nits to candela per square meter for display luminance.
Convert lamberts to candela per square meter.
Calculate electrostatic force between two point charges.
Calculate electric field strength from point charges and distributions.
Calculate electric potential from point charges at a given distance.
Calculate capacitance of a parallel plate capacitor from area and gap.
Calculate capacitance of a spherical or concentric sphere capacitor.
Calculate capacitance of a cylindrical (coaxial) capacitor.
Calculate energy stored in a capacitor from capacitance and voltage.
Calculate energy stored in an inductor from inductance and current.
Calculate the force on a current-carrying wire in a magnetic field.
Calculate magnetic field from a current element using Biot-Savart law.
Calculate magnetic field using Ampere law for symmetric geometries.
Calculate induced EMF from changing magnetic flux using Faraday law.
Determine direction of induced current using Lenz law.
Calculate self-inductance of solenoids and toroidal coils.
Calculate mutual inductance between two coupled coils.
Analyze series and parallel RLC circuits for resonance and impedance.
Calculate complex impedance of R, L, C circuit elements at a frequency.
Calculate inductive and capacitive reactance at a given frequency.
Calculate resonant frequency of LC and RLC circuits.
Calculate skin depth for AC current in conductors at a given frequency.
Calculate electromagnetic wave impedance in free space and media.
Calculate antenna gain and effective aperture from specifications.
Calculate received power between antennas using the Friis equation.
Calculate maximum radar detection range from system parameters.
Calculate end-to-end link budget for wireless communication systems.
Reference for circuit breakers: single-pole, double-pole, GFCI, and AFCI breakers.
Reference for fuse types: cartridge, plug, blade, and time-delay fuses.
Reference for switch types: toggle, rocker, dimmer, 3-way, and 4-way switches.
Reference for outlet types: duplex, GFCI, USB, tamper-resistant, and weather-resistant.
Reference for plug types worldwide: Type A through N with voltage and frequency.
Reference for wire types: THHN, NM-B, UF-B, and MC cable with gauge ratings.
Reference for conduit types: EMT, IMC, rigid, PVC, and flexible conduit.
Reference for junction boxes: metal, PVC, old work, new work, and sizing rules.
Reference for electrical panels: main breaker, main lug, sub-panels, and sizing.
Reference for disconnect switches: fusible, non-fusible, and safety switch types.
Reference for transfer switches: manual, automatic, and load management types.
Reference for surge protectors: Type 1, 2, and 3 with joule ratings and clamping.
Reference for ground fault protection: GFCI devices, locations, and testing.
Reference for arc fault protection: AFCI breakers, outlets, and code requirements.
Reference for transformer types: step-up, step-down, isolation, and auto-transformers.
Reference for relay types: electromechanical, solid-state, reed, and time-delay.
Reference for contactors: definite purpose, lighting, and NEMA size ratings.
Reference for motor starters: DOL, star-delta, soft starter, and VFD starting.
Reference for variable frequency drives: sizing, parameters, and fault codes.
Reference for programmable logic controllers: I/O types, ladder logic, and brands.
Reference for sensor types: temperature, pressure, flow, level, and position sensors.
Reference for actuator types: electric, pneumatic, hydraulic, and piezoelectric.
Reference for solenoids: AC, DC, push, pull, and rotary solenoid types.
Reference for thermocouple types: J, K, T, E, N, S, R, and B with temp ranges.
Reference for RTD sensors: PT100, PT1000, 2-wire, 3-wire, and 4-wire configs.
Reference for strain gauges: foil, wire, semiconductor, and Wheatstone bridge.
Reference for proximity sensors: inductive, capacitive, magnetic, and optical types.
Reference for photoelectric sensors: through-beam, retro-reflective, and diffuse.
Reference for ultrasonic sensors: proximity, distance, level, and flow measurement.
Reference for encoder types: incremental, absolute, linear, and rotary encoders.
Reference for wire nuts: color coding, wire gauge ranges, and torque specs.
Reference for electrical boxes: single, double, round, and box fill calculations.
Reference for switch plates: standard, decorator, combo, and oversized covers.
Reference for outlet covers: duplex, decorator, weatherproof, and floor box types.
Reference for blank plates: standard, decorator, weatherproof, and jumbo sizes.
Reference for weatherproof boxes: in-use covers, bubble covers, and NEMA ratings.
Reference for recessed cans: IC, non-IC, airtight, and LED retrofit trim types.
Images, PDFs, video, audio, text, code, calculators, SEO, and more. All free, all in your browser.
Explore All Tools