Electrical Calculators
Check conduit fill, residential dwelling demand and electrical box volume with three free electrical calculators. Choose the check you need and review the calculation basis alongside your project requirements.
Available calculators
3 live toolsCheck a selected raceway or find a minimum conduit trade size for the supported conductors.
- Mixed conductor sizes
- EMT, IMC, RMC and PVC
- Fill percentage and minimum size
2026 NEC Chapter 9 basis; verify project requirements.
Open CalculatorCalculate connected general load, demand and HVAC load for the supported dwelling method.
- Connected and demand VA
- HVAC comparison and total kVA
- Calculated amps at selected voltage
2023/2026 basis selector; no automatic service or conductor sizing.
Open CalculatorCompare required conductor and device fill with standard or marked box volume.
- #18–#6 AWG allowances
- Devices, EGCs and terminal assemblies
- Required, available and spare volume
2023 NEC 314.16 basis; PASS is not universal code approval.
Open CalculatorChoose the right electrical check
Raceway fill, dwelling load and box fill answer different questions. Use conductor sizes, nameplate loads and marked box information from the project; one calculation does not replace the others.
Verify the adopted NEC edition and AHJ amendments. These tools do not establish compliance or select breakers, feeders or service ratings.
When the drawing set needs a takeoff
A full electrical takeoff coordinates raceways, conductors, devices, fixtures and gear with plans and schedules. It also captures separate systems and scope notes that a focused calculator cannot identify.
For bid pricing, pair the measured quantities with project labor, supplier information and specifications.
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Send your drawings, specifications and scope to Build IT Estimating for a project takeoff or estimate.
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