Electrical Engineering
Ohm's law, power, batteries, cables, transformers, solar.
A professional Electrical Engineering suite — Ohm's law, AC/DC power, batteries, resistors, cable sizing & voltage drop, transformers, motors, generators, and solar renewables. Offline-first, IEEE/IEC-referenced, and print-ready.
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Most used in Electrical.
Ohm's Law Calculator
Solve V, I, R, and P from any two known values.
Watt Calculator
Compute electrical power from any two of V, I, R.
Voltage Calculator
V = I · R from Current and Resistance.
Current Calculator
I = V / R from Voltage and Resistance.
Power Calculator
Real power single- or three-phase with power factor.
Energy Consumption Calculator
kWh per day, month, and year for any appliance.
Electricity Bill Calculator
Total bill from usage, tariff, fixed charge, and tax.
Single Phase Power Calculator
P = V · I · pf for single-phase supplies.
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Recently added.
Solar Payback Calculator
Years to recover install cost from savings.
Solar Inverter Calculator
Continuous rating with headroom & surge.
Solar Battery Sizing Calculator
Battery bank size for autonomy days.
Solar Energy Calculator
Daily / monthly / yearly PV production.
Solar Panel Calculator
Number of panels for a daily load.
Generator Calculator
Recommended generator kVA rating with headroom.
Motor Efficiency Calculator
η = P_out / P_in.
Motor Power Calculator
hp ↔ W, shaft and input power.
All Electrical Engineering
40 tools available.
Battery Backup Time Calculator
Hours a battery powers a given load.
Cable Size Calculator
Conductor area (mm²) for an allowed voltage drop.
Electricity Bill Calculator
Total bill from usage, tariff, fixed charge, and tax.
LED Resistor Calculator
Series resistor for any supply + LED forward voltage.
Motor Current Calculator
Full-load current from power, V, pf, efficiency.
Ohm's Law Calculator
Solve V, I, R, and P from any two known values.
Power Calculator
Real power single- or three-phase with power factor.
Resistor Color Code Calculator
Ω → 4-band color code with tolerance.
Solar Battery Sizing Calculator
Battery bank size for autonomy days.
Solar Panel Calculator
Number of panels for a daily load.
Three Phase Power Calculator
P = √3 · Vₗ · Iₗ · pf for three-phase systems.
Voltage Drop Calculator
ΔV across copper or aluminium conductor.
FAQ
About Electrical Engineering.
Do these electrical calculators need an internet connection?
No. Every Ohm's law, power, battery, cable, transformer, motor, and solar calculator runs 100% client-side using pure formula engines. Nothing is uploaded, cached, or logged.
Which standards do the formulas follow?
Formulas follow IEEE and IEC 60050 conventions. AWG uses the ASTM B258 relation d(AWG) = 0.127 · 92^((36 − AWG)/39) mm. Voltage-drop uses copper (1.724 × 10⁻⁸ Ω·m) or aluminium (2.82 × 10⁻⁸ Ω·m) resistivity with a temperature-coefficient correction.
Can I export or print the results?
Yes. Every calculator produces Markdown, CSV, JSON, and plain-text artifacts you can copy, download, print, or share — including step-by-step formula reports and safety notes.
Are these calculators a substitute for a licensed electrician?
No. Results are engineering estimates for sizing, teaching, and preliminary design. Real installations must follow your local electrical code (NEC, IEC, BS 7671, etc.) and be certified by a licensed professional.
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