Working calculators
Live tools that update as you type. Do the math before you buy wire or pull a permit — always confirm against the current CEC and your local ESA amendments before sizing a real circuit.
Ohm's Law Solver
Enter any two of V, I, R — solves the rest plus wattage in real time. On the homepage.
● LiveWire Gauge & Ampacity (NMD90)
Match conductor size to breaker rating — copper NMD90, CEC Table 2.
● LiveBreaker Size
Watts or amps in — minimum standard breaker out, with the 125% continuous-load rule built in.
● LiveVoltage Drop
Check run length against conductor size — flags anything over the 3%/5% guideline.
● LiveCEC Direct Burial & Trench Depth
Mandatory cover depth, NMWU/TECK90 cable selection, and conduit rules — CEC Table 53.
Panel Load Calculation
Estimate total demand load for a dwelling per CEC Section 8.
● LiveLoad (Home / Room / Circuit)
Break demand load down by room or by individual circuit.
● LiveService Size (100A / 200A / 400A)
What service size a home actually needs based on its total load.
● LivePanel Fill
How many spaces are left, and whether a sub-panel makes sense.
● LiveConduit Fill
How many conductors a given conduit size can legally carry.
● GuideBox Fill
Understand conductor, device, clamp, and grounding volume inside electrical boxes.
● LiveFault Current
Estimate available fault current for breaker/panel rating checks.
● LiveGFCI/AFCI Requirement
Answer "does this circuit need it" directly from inputs.
● LiveOutlet Load (Amps per Device)
How many devices a receptacle circuit can realistically carry.
Electricity Cost (kWh — $)
Convert usage into an actual dollar estimate at your rate.
● LiveAppliance Energy Usage
What a given appliance is really costing you per month.
● LiveSpace Heater Cost
Running cost for a portable space heater by wattage and hours.
● LiveDehumidifier Cost
Running cost estimate by unit size and usage.
● LiveAir Conditioner Cost
Running cost estimate by unit size and usage.
● LiveWhole-Home Energy Load
Roll every major appliance into one household load picture.
Breaker Trip Diagnosis
Walks through the likely cause based on how and when it trips.
● LiveFlickering Light Diagnosis
Narrows down the likely cause from a few quick inputs.
● LiveWarm Outlet Risk
Flags how urgent a warm outlet or cover plate really is.
● LivePower Surge Risk
Estimate exposure and whether whole-home surge protection makes sense.
● LiveArc Fault Risk
Rough risk read based on wiring age and circuit type.
● LiveOverloaded Circuit
Add up connected devices against the circuit's rated capacity.
EV Charger Load (40A/48A/60A)
Size the circuit for common Level 2 EV charger amperages.
● LiveEV Charger Panel Upgrade
Whether adding a charger pushes you past what your panel can handle.
● LiveSolar System Load
Rough sizing reference for a home solar setup.
● LiveGenerator Sizing
Match a backup generator to your must-run circuits.
● LiveTransfer Switch Load
Size a transfer switch against your generator and panel.
● LiveBattery Backup Runtime
Estimate runtime for a home battery backup under a given load.
Pot Light Spacing
Layout spacing based on room size and ceiling height.
● LiveLumens Required Per Room
How much light a given room actually needs.
● LiveFixture Wattage
Total wattage across a lighting circuit or fixture group.
● LiveLED Conversion (Watts — Lumens)
Translate old incandescent watts into the LED equivalent.
● LiveOutdoor Lighting Load
Add up exterior fixtures against the feeding circuit.
● LiveChandelier Size
Fixture size and weight guidance against box rating and room scale.
Basement Wiring Load
Plan circuits for a basement finishing project.
● LiveKitchen Renovation Electrical Load
Countertop, appliance, and lighting load for a kitchen reno.
● LiveBathroom Renovation Electrical Load
GFCI, fan, and lighting load for a bathroom reno.
● LiveLighting Layout (# of Pot Lights)
How many fixtures a given room layout needs.
● LiveRoom Circuit Planner
Rough out how many circuits a renovated room needs.
● LiveAppliance Load (Kitchen)
Add up major kitchen appliances against circuit capacity.
● LiveHeat Pump / AC Load
Size the circuit for a heat pump or central AC unit.
● LiveElectric Heater Load
Size the circuit for a fixed electric heater.
● LiveHot Tub / Spa Electrical
Permit-flagged reference for hot tub and spa circuits.