Electrical
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Electricity Cost

Estimate monthly electricity cost by appliance usage

energybillpower

Wire Size

Select the right wire gauge for your electrical circuit

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Voltage Divider

Design voltage divider circuits with resistor values

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Ohm's Law

Calculate voltage, current, and resistance using Ohm's Law

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LED Resistor

Calculate the right resistor for LED circuits

electronicslightingcircuit

Resistor Color Code

Decode resistor values from color bands or find colors

bandselectronicscomponents

Generator Sizing Calculator

Size a backup generator by your power requirements

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Circuit Breaker Size Calculator

Calculate the right breaker size per NEC code

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Conduit Fill Calculator

Calculate conduit fill percentage per NEC standards

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Solar Panel Size Calculator

Calculate how many solar panels you need by usage

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EV Charger Sizing Calculator

Size EV charger circuits per NEC 625 — breaker size, wire gauge, panel capacity, and charging time for Level 1 and 2 EVSE

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Electrical Panel Load Calculator

Calculate residential electrical panel load per NEC Article 220 with demand factors, service sizing, and capacity analysis

panel loadelectrical panelservice size

Lighting Layout Calculator

Calculate recessed light fixture count and spacing for any room using the zonal cavity method — foot-candles, lumens, and grid layout

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Ground Fault Calculator

Check NEC 2020 GFCI and AFCI requirements by room type — determine required outlet count, applicable code sections, and protection costs

GFCIground faultAFCI

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