Free Electrical & Electronics Calculator Widgets
Ohm's law, power, three-phase, voltage drop, wire gauge, resistor, battery and solar widgets for electricians, engineering students and solar installers.
Who these are for
Electricians, engineering students, electronics hobbyists and solar installers.
Common uses
- In a wiring guide to estimate voltage drop before choosing a cable
- On a solar installer's site to size a system from a monthly bill
- In electronics tutorials for LED resistors and resistor colour codes
How embedding works
Pick a widget, set the theme and size, copy one line of HTML and paste it into your page. It runs in its own frame, so it cannot clash with your site's styles, and it resizes itself if you use the loader.
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Enter any two of voltage, current, resistance and power to get the other two.
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Watts, volt-amps and amps for DC and single-phase AC circuits, with power factor.
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kW, kVA and kVAR from line voltage, current and power factor - or the current from kW or kVA.
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Volts and percent lost along a copper or aluminium cable, for DC, single-phase and three-phase runs.
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Convert AWG to mm2, diameter in mm and inches, circular mils and copper resistance.
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Output voltage of a two-resistor divider, or the R2 needed for a target voltage, with an optional load.
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Series resistor for one LED or a string: standard E12/E24 value, real current and power rating.
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Read 4, 5 and 6-band resistor colour codes, or find the bands for a value.
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Equivalent of up to 8 resistors or capacitors in series or in parallel.
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kVA, kVAR and phase angle from kW and power factor, plus the capacitor kVAR to reach a target.
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How long a battery runs a load, from Ah, voltage, depth of discharge and efficiency.
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Backup time of a home inverter or UPS battery bank, or the battery Ah needed for the hours you want.
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Panels and system kW needed to cover your energy use, from your own peak sun hours.
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Daily, monthly and yearly running cost of up to 8 appliances at your tariff.
No widget matches that search.
Other widget categories
How to add a widget
Open a widget, choose the theme, width and style, check the live preview, then copy the code. Paste it into an HTML or "Custom code" block on your site - step-by-step instructions for each platform.