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Showing 34 of 34 calculators

I am a(n):

NEC compliant voltage drop with parallel conductors, temperature-corrected resistance, and Cu/Al support.

210.19(A)Wire & Conduit

Wire Size Calculator

Find the correct wire gauge with auto-parallel conductor detection and temperature/fill derating per NEC 310.16.

310.16Wire & Conduit

Calculate fill for EMT, PVC, RMC, IMC, FMC, and LFMC conduits with THHN, THWN-2, XHHW, RHW conductors.

Chapter 9Wire & Conduit

Wire Pulling Tension

Estimate cable pulling tension based on run length, cable weight, and total bend degrees for safe conduit pulls.

358.26Wire & Conduit

Cable Tray Fill

Calculate cable tray fill for ladder, ventilated trough, and solid bottom trays per NEC 392.22.

392.22Wire & Conduit

Residential service load per NEC 2023 & 2026. Standard and optional methods with conductor sizing.

220Load Calculations

Commercial Load

Calculate commercial service load per NEC Article 220 Part IV with demand factors for lighting, receptacles, kitchen, and HVAC.

220 Part IVLoad Calculations

Calculate dwelling unit demand load per NEC Article 220 for service sizing.

220Load Calculations

Load Calculator

Calculate electrical load for branch circuits and service entrance sizing.

220Load Calculations

Estimate electricity costs based on power consumption, usage time, and utility rates.

Load Calculations

Full motor circuit calculator: FLC, OCPD, overload, NEMA starter sizing, and locked-rotor current per NEC 430.

Size standby and portable generators based on connected loads.

Estimate incident energy (cal/cm2) and PPE category per IEEE 1584 and NFPA 70E.

NFPA 70ESafety & Protection

Short Circuit / AIC

Calculate available fault current at the load using point-to-point method for breaker AIC selection.

110.9Safety & Protection

Transformer OCPD

Size overcurrent protection for transformers per NEC 450.3. Supports supervised/unsupervised locations.

450.3Safety & Protection

Circuit Breaker Size

Determine the correct circuit breaker size based on load current and NEC requirements.

240Safety & Protection

Grounding Conductor

Size equipment grounding conductors per NEC Table 250.122.

250.122Safety & Protection

Conduit Bending

All 8 bend types: offset, 90 stub-up, back-to-back, 3-point saddle, 4-point saddle, kick, rolling offset, segmented.

Chapter 9Conduit Bending

Pull Box Sizing

Calculate minimum pull box dimensions for straight, angle, and U-pulls per NEC 314.28.

314.28Conduit Bending

Calculate junction box, device box, and outlet box fill per NEC Article 314.16.

314.16Conduit Bending

NEMA Configurations

Visual reference for NEMA wiring configurations and wire color codes for 120/240V, 277/480V, and 120/208V.

Calculate voltage, current, resistance, and power using Ohm's Law. Enter any two values to find the rest.

Resistance Calculator

Calculate total resistance for series and parallel resistor combinations.

Voltage Divider

Calculate output voltage for resistive voltage divider circuits.

Three-Phase Power

Calculate three-phase power, current, and voltage for balanced three-phase electrical systems.

Calculate power factor, reactive power, and apparent power for AC circuits.

Calculate the correct current-limiting resistor for LED circuits.

Transformer Calculator

Size transformers and calculate turns ratio, primary/secondary voltages and currents.

Battery Runtime

Calculate battery backup runtime based on capacity and load requirements.

Project Builder

Chain calculations together and generate professional multi-page engineering submittals for inspectors.

Size solar photovoltaic systems including inverter sizing, conductor sizing, and overcurrent protection per NEC 690.

690Wire & Conduit

Size electrical service, branch circuits, and overcurrent protection for electric vehicle charging stations per NEC 625.

625Load Calculations

Battery Storage

Size battery energy storage systems including conductors, overcurrent protection, and disconnects per NEC 706.

Create and balance panel schedules with automatic load totals, phase balancing, and circuit directory generation.

Get More in the App

All calculators work offline. Plus NEC code lookup, OJT hour tracking, exam prep, and more. Free to download.

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Why Use SparkShift Calculators?

Built by licensed electricians using NEC 2023 code requirements. Unlike generic calculators, our tools are designed specifically for the electrical trade.

Real NEC Table Data

Ampacities, conduit areas, and wire sizes from actual code tables

Derating Factors

Temperature correction and conduit fill adjustments built-in

Code References

Know exactly which NEC article your calculation is based on

Mobile-First Design

Works great on phones at the jobsite

Calculators Every Electrician Needs

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Conduit Bending

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