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Engineering Calculators
Every calculator includes step-by-step solution breakdown, formula references, and real engineering standards citations.
Electrical
Ohm's Law Calculator
Solve for voltage, current, or resistance. Includes power dissipation and Show Your Work panel.
V = I × R
Electrical
Voltage Divider Calculator
Calculate output voltage, current, power dissipation, and divider ratio from two resistors.
Vout = Vin × R2/(R1+R2)
All Disciplines
Engineering Unit Converter
Convert between Imperial and SI units across 8 categories including pressure, force, flow, and temperature.
Imperial ↔ SI
Electrical
Wire Gauge & Ampacity
Find the correct AWG wire size for your load per NEC Article 310. Includes temperature and bundling derating.
NEC 2023 Article 310
Mechanical
Horsepower & Torque
Solve for power, torque, or RPM. Supports Imperial (HP/lb·ft) and SI (kW/N·m) units. SAE J1349 referenced.
HP = T × N / 5252
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15 More Calculators
Beam deflection, Reynolds number, pipe flow, gear ratio, and more
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Show Your Work
Every calculator shows a complete step-by-step solution breakdown — not just an answer. Because engineers need to verify, document, and explain results.
Standards Referenced
Formulas cite IEEE, ASME, NEC, ASTM, and AISC standards. You always know where the math comes from and when it applies.
Assumptions & Limits
Every calculator clearly states its assumptions, limitations, and when NOT to use it. No other calculator site does this. We do it because it matters.
Imperial & SI
Toggle between unit systems with a single click. Input validation catches errors before they become expensive mistakes.
Coverage
8 Engineering Disciplines
Calculators for every major engineering field, built to professional standards.
Electrical
6 calculators
Mechanical
4 calculators
Civil / Structural
4 calculators
Chemical
2 calculators
Thermodynamics
2 calculators
Fluid Mechanics
2 calculators
General / Conversions
1 calculator
Electronics
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