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Plan safely.Calculations are estimates, not a permit, inspection, or substitute for a licensed electrician.
CALCULATORS
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Results update when you calculate. Inputs stay on your device.
01
Voltage Drop Calculator
Estimate conductor voltage loss for a two-wire copper circuit. Use one-way distance; the calculator accounts for the return path.
Estimated drop
3.57 V2.98% • approximately 116.43 V at load02
Energy Cost Calculator
See what an appliance, tool, heater, or other electrical load may add to an electric bill.
Estimated monthly cost
$32.40180.0 kWh used in 30 days03
LED Lighting Savings
Compare existing fixture wattage with a proposed LED replacement and estimate annual savings.
Estimated annual savings
$1,048.325,824 kWh and 2.24 kW of connected load reduced04
Ohm's Law Calculator
Enter voltage and resistance to calculate current and power for a simple resistive DC circuit.
Calculated current
10.00 A1,200 watts of calculated power05
Electrical Power Calculator
Estimate real power from voltage, current, phase, and power factor. Balanced-load assumptions apply for three-phase results.
Estimated real power
9.73 kW10.81 kVA apparent power06
Transformer Current Calculator
Convert a transformer's kVA and line voltage into estimated full-load current for single- or three-phase systems.
Estimated full-load current
90.21 ABased on nameplate kVA and balanced voltage07
Generator Size Estimator
Add simultaneous running watts and the largest additional starting surge. The result includes your chosen planning reserve.
Planning target
10.2 kW8.5 kW calculated peak before reserve08
EV Charging Cost
Estimate wall energy and cost from battery energy added, charging efficiency, and your electric rate.
Estimated cost per charge
$12.00$48.00 per month • 66.7 kWh from the wall per charge09
Breaker Load Planner
Convert a single-phase load to amperes and compare it with common breaker ratings. Continuous loads receive a 125% planning factor.
Adjusted planning load
18.75 ANext planning reference: 20 A • verify conductors and equipment rules10
Electrical Project Estimator
Combine labor, materials, material markup, fixed costs, and material tax for a transparent planning estimate.
Planning estimate
$2,703.81Labor $1,520.00 • materials/markup/tax $1,033.81 • fixed $150.0011
Conduit Bending Calculator
Calculate field measurements for offsets, rolling offsets, three-point saddles, and 90° stub-ups.
Distance between marks
12.00 in½-inch EMT • 30° offset • 1.50 in shrink • multiplier 2.000NO PAID AI REQUIRED
Fast answers without guessing
KNOW WHAT THE NUMBER MEANS
Good calculations support good decisions.
Voltage drop
Longer runs, higher current, and smaller conductors increase voltage loss. Check equipment requirements and applicable codes before selecting conductors.
Energy use
Utilities bill by kilowatt-hour. One kilowatt-hour equals 1,000 watts operating for one hour. Your actual bill may also include fees and variable rates.
Lighting upgrades
Wattage savings are only one part of a retrofit. Verify light output, color, controls, emergency operation, compatibility, and disposal requirements.
Motors and starting loads
Motors and compressors can draw substantially more power while starting. Use manufacturer data when planning generators, feeders, and protective equipment.
Single vs. three phase
Three-phase calculations include the square root of three when line-to-line voltage is used. Unbalanced loads require phase-by-phase review.
Estimates are not designs
Calculated values help compare options. Final installations still require equipment instructions, adopted codes, permits, inspections, and qualified judgment.
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WireWise Tools turns common electrical planning questions into clear estimates. The site is shaped by real-world electrical work experience, with calculators designed to show assumptions and explain what a result can—and cannot—tell you.
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Pages are created to solve a specific problem. Automated assistance may support drafting or calculations, but safety guidance and technical claims require human review before publication.