Are these calculators free?

Yes. Every tool is free to use, needs no sign-up, and runs in your browser.

Do you store my data?

No. Calculations happen locally in your browser; we don't upload the values you enter to a server.

Do these tools replace an electrician?

No. VoltTally provides planning estimates and makes assumptions visible. Confirm final designs and code requirements with a qualified professional.

Circuits. Charging. Cost. Comfort.

Size it once. Power it with confidence.

Free, accurate calculators for electrical projects and home-energy planning. Test the numbers before you buy wire, equipment, or another month of energy.

Run a quick estimate Check methodology

What are you planning?

Choose a project lane to reach the calculator built for that decision.

Circuit planning Voltage drop and wire size EV charging Equipment and install cost Running cost Appliances and electricity Heating Heat-pump cost planning

Quick energy check

Appliance Running Cost

Use the appliance wattage, daily runtime, and your electric rate for a fast monthly cost estimate.

Estimated running cost —

Voltage Drop Check drop percentage and conductor options for a run. Open EV Charger Cost Scope hardware, labor, permits, routing, and panel work. Open

6 live calculators

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Planning with limits

Assumptions stay visible.

VoltTally explains source dates, planning limits, and the inputs behind each result. Electrical outputs support project planning—not code approval.

Our methodology Report a correction

Full toolkit

Every calculator has one clear job.

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01 Voltage Drop Check voltage drop % and size conductors for any run — copper or aluminum, single- or three-phase. 02 Wire Size Find the right wire gauge for a given current, distance, and voltage-drop limit. 03 EV Charger Cost Estimate a Level 2 home EV charger install — hardware, labor, and panel work. 04 Panel Load Compare existing demand with an EV charger and heat pump, then prepare panel-capacity and load-management questions for an electrician. 05 Running Cost See what any appliance costs to run per hour, day, month, and year at your rate. 06 Heat Pump Cost Estimate heat-pump install cost and running cost vs your current system.