Every Electrician Calculator, in One Place
Free, NEC-compliant calculators for conduit fill, voltage drop, breaker sizing, grounding, and more — plus dedicated sizing guides for specific appliances and equipment.
Core Calculators
Breaker Size Calculator
Find the correct breaker and wire size for your circuit per NEC ampacity tables.
Open CalculatorConduit Fill Calculator
Calculate NEC-compliant conduit fill percentages for EMT, PVC, RMC, and FMC.
Open CalculatorVoltage Drop Calculator
Determine voltage drop across wire runs using the NEC K-factor method.
Open CalculatorBox Fill Calculator
Verify NEC 314.16 junction and device box fill compliance instantly.
Open CalculatorGrounding Calculator
Size EGC and GEC conductors per NEC Table 250.122 and Table 250.66.
Open CalculatorConduit Bending Calculator
Calculate offset, saddle, and stub-up bend marks for EMT and rigid conduit.
Open CalculatorEV Charger Calculator
Size a Level 2 EV charger circuit and check panel capacity per NEC 625.42.
Open CalculatorWire Gauge Chart
Reference AWG diameters, cross-sectional areas, and NEC ampacity ratings.
Open CalculatorBreaker Sizing — Specific Sizing Guides
Electric Range Circuit Breaker & Wire Size
What size breaker does an electric range need? Standard ranges require a 40A or 50A double-pole breaker on a dedicated 240V circuit per NEC.
Open CalculatorElectric Water Heater Breaker & Wire Size
What size breaker does a water heater need? Standard 4500W electric water heaters require a 30A double-pole breaker with 10 AWG copper wire per NEC rules.
Open CalculatorElectric Dryer Breaker & Wire Size
Standard electric dryers require a 30 amp double-pole breaker with 10 AWG copper wire on a 240V circuit. Learn how to size your dryer circuit.
Open CalculatorStandard Breaker Sizes NEC & Fuse Ratings
Standard breaker sizes per NEC 240.6(A). Comprehensive chart of standard circuit breaker amperage ratings from 15A to 6000A for residential & commercial.
Open Calculator3-Phase Circuit Breaker & Wire Size Calculator
Calculate 3-phase circuit breaker and wire size. Supports 208V, 240V, and 480V three-phase systems for motors, heaters, and continuous commercial loads.
Open CalculatorHot Tub & Spa Breaker Size (NEC Article 680)
What size breaker does a hot tub need? Most hardwired 240V spas require a 50 amp GFCI breaker with 6 AWG copper wire per NEC Article 680.
Open CalculatorRV Breaker Size: 30 Amp vs 50 Amp Service
What size breaker for an RV outlet? 30A service uses a single-pole 120V breaker with 10 AWG wire; 50A service uses a double-pole breaker with 6 AWG wire.
Open CalculatorDuctless Mini Split Breaker & Wire Size
What size breaker for a mini split AC unit? Sizing depends on the manufacturer's MCA/MOCP nameplate rating per NEC 440, typically 15A to 30A.
Open CalculatorBuilt-In Electric Wall Oven Breaker & Wire Size
What size breaker for a built-in wall oven? Most single wall ovens need a 20A-30A double-pole 240V breaker; double wall ovens often require 30A-40A.
Open CalculatorGarbage Disposal Breaker & Wire Size
What size breaker for a garbage disposal? Most residential disposals require a dedicated 15A or 20A 120V circuit with 14 or 12 AWG copper wire.
Open CalculatorSubmersible Well Pump Breaker & Wire Size
What size breaker for a well pump? Sizing depends on motor horsepower and full-load amps per NEC Article 430, typically 15A to 30A for residential pumps.
Open CalculatorDishwasher Breaker & Wire Size
What size breaker for a dishwasher? Most residential dishwashers need a dedicated 15A or 20A 120V circuit with GFCI protection per NEC 210.8(D).
Open CalculatorConduit Fill — Specific Sizing Guides
1-1/2" Conduit Wire Fill Calculator
Calculate how many wires fit in 1.5 inch conduit. Free 1-1/2" EMT, PVC Schedule 40/80, and RMC fill calculator per NEC 40% fill rule for 3+ conductors.
Open Calculator1-Inch Conduit Wire Fill Calculator
Calculate how many wires fit in 1 inch conduit. Free 1" EMT and PVC fill calculator per NEC 40% fill rules. Instantly check capacity for any wire gauge.
Open CalculatorCat 6 & Low-Voltage Conduit Fill Calculator
Calculate how many Cat 6 or Cat 6a ethernet cables fit inside EMT or PVC conduit. Compliant with NEC 40% fill rule for low-voltage communications wiring.
Open CalculatorVoltage Drop — Specific Sizing Guides
EV Charging — Specific Sizing Guides
Tesla Wall Connector Circuit Breaker & Wire Size
What size breaker and wire for a Tesla Wall Connector Gen 3? The 48A charger requires a 60A breaker and 6 AWG copper wire per NEC 625.42.
Open CalculatorNEMA 14-50 Outlet: Breaker & Wire Size Guide
What wire size and breaker for a NEMA 14-50 outlet? Requires a 50A double-pole breaker and 6 AWG copper wire for EV charging and RV hookups per NEC rules.
Open CalculatorGrounding — Specific Sizing Guides
Ground Wire Size for a 200 Amp Panel
What size ground wire for a 200 amp panel? GEC is typically 4 AWG copper per Table 250.66. Feeder EGC for 200A sub-panel is 6 AWG copper per Table 250.122.
Open CalculatorNEC Table 250.66 Grounding Electrode Conductor Table Explained
NEC Table 250.66 explained: how to size the grounding electrode conductor (GEC) based on service-entrance conductor size, for any electrical service.
Open Calculator