All Solar and Electrical Calculators

Solar sizing

Balcony Solar Calculator: Estimate yearly output, savings and payback for a plug-in balcony solar kit with an 800 W inverter, from your location and mounting.
How Many Solar Panels Do I Need Calculator: Work out how many solar panels you need from your yearly or monthly kWh use, your location or peak sun hours, and the panel wattage.
Solar Panel Calculator: Find the solar system size, panel count and yearly output you need from your bill or kWh use, using real sun data for your location.
Solar Panel Output Calculator: Estimate the kWh your solar panels produce per day, month and year from system size, location, tilt, direction and losses.

Electricity Cost Calculator: Find what any appliance costs to run per hour, day, month and year from its watts, hours of use and your electricity rate.
Net Metering Calculator: Compare your monthly electric bill under net metering and net billing from imported and exported kWh, retail and export rates.
Solar Panel Cost Calculator: Estimate installed solar cost before and after incentives in the US, UK, Australia or Germany, with dated default prices per watt.
Solar Payback Calculator: Calculate solar payback years, 25-year savings and ROI from system cost, production, self-consumption, rates, price rises and degradation.
STC Calculator: Calculate how many STCs your Australian solar system or home battery earns and what the rebate is worth, using current CER rules.

Ah to Wh Calculator: Convert amp-hours to watt-hours, or watt-hours to amp-hours, for 12 V, 24 V and 48 V batteries.
Amp Hour Calculator: Size a battery in amp-hours for a DC load and runtime, or find how long a battery of known Ah will last.
Battery Backup Calculator: See how long a home battery, UPS or power station will keep your essential loads running during a power outage.
Battery Calculator: Size a solar or backup battery bank in Ah and kWh from your daily load, days of autonomy and depth of discharge, with the series and parallel layout.
Battery Life Calculator: Estimate how many hours a LiFePO4, AGM or flooded battery will run a load, with depth of discharge and inverter losses included.
mAh to Wh Calculator: Convert milliamp-hours to watt-hours for power banks, phone batteries and battery packs, and check the 100 Wh airline limit.

Amps to Watts Calculator: Convert amps to watts for DC, single-phase and three-phase AC loads using voltage and power factor.
kVA to kW Calculator: Convert kVA to kW with any power factor and see the reactive power in kVAR for generators, UPS units and transformers.
kW to Amps Calculator: Convert kilowatts to amps for DC, single-phase and three-phase AC systems at any voltage and power factor.
kWh Calculator: Work out the kilowatt-hours any device uses from its power and run time, and see what that energy costs at your electricity rate.
Voltage Drop Calculator: Calculate voltage drop and percent drop for copper or aluminum wire in DC, single-phase and three-phase circuits, by AWG or mm².
Watts to Amps Calculator: Convert watts to amps for DC, single-phase and three-phase AC circuits, with power factor and line-to-line voltage built in.
Watts to kWh Calculator: Convert an appliance's watts into kilowatt-hours per day, month and year from the hours it runs.
Wire Size Calculator: Find the minimum copper or aluminum wire gauge that meets both NEC ampacity and your voltage drop limit, in AWG and mm².

Inverter Size Calculator: Work out the continuous and surge rating your inverter needs, the DC current at 12, 24 or 48 V, or a grid-tie inverter size from your DC/AC ratio.
Solar String Size Calculator: Find the minimum and maximum number of solar modules per string from temperature-corrected Voc and Vmp and your inverter voltage limits.

Charge Controller Calculator: Size an MPPT or PWM solar charge controller in amps and check the cold-weather string voltage against its PV input limit.
Solar Generator Calculator: Pick the right solar generator or portable power station size from your appliances, and see how long your panels take to recharge it.

Peak Sun Hours Calculator: Find the average peak sun hours per day at your location, month by month, for an optimal, latitude, flat or custom panel tilt.
Solar Panel Angle Calculator: Find the best fixed tilt angle for solar panels at your location from PVGIS, with the latitude rule, seasonal angles and the yield on your own roof.