The math and repair plan in one place.
Calculators, code reference, a date-based study planner, and a score-report decoder. Built to be useful on the test and on the job. The math is the math, and the plan should match the clock.
Planning tools
Exam Date Study Plan
State-aware planning
Pick your state, exam date, weekly study time, and weakest area. Get a 7, 14, 30, or 60 day study block.
Open toolScore Report Decoder
Retake repair plan
Pick your state, score band, and weakest line. Get the first seven-day repair block before you buy more prep.
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Calculators
Voltage Drop
Chapter 9 Table 8 + 210.19(A)
Round-trip math for selected conductors. The single-phase 2 multiplier is where many exam misses start.
Open calculatorWire Size
Chapter 9 Table 8
Find the next listed conductor size for a voltage-drop target. Copper or aluminum, single phase or three phase.
Open calculatorAmpacity
310.16 + 310.15 + 110.14(C)
Table 310.16 base ampacity, ambient correction, conductor adjustment, and terminal temperature cap.
Open calculatorBox Fill
Article 314.16
Counting conductors, grounds, and yokes. One ground equals one count. Yokes count as two.
Open calculatorConduit Fill
Chapter 9 Tables 1, 4, 5
53% for one conductor. 31% for two. 40% for three or more. Then Chapter 9 Table 4 for raceway area.
Open calculatorDwelling Load
Article 220
3 VA per square foot. Two SAs and a laundry. First 3,000 at 100%, the rest at 35%.
Open calculatorElectrical Load
Article 220
Residential dwelling service-load math: square footage, required circuits, large appliances, heat versus AC, EVSE, and service size.
Open calculatorTransformer Sizing
Transformer kVA + current
Solve kVA from amps or amps from kVA. Single-phase and three-phase transformer math with the setup shown.
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Same exam math, different search terms
Electricians search for the same math in different words. Use this map when you know the problem but not the exact NEC name.
Quick Reference
External Resources
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