Engineering Calculators
Practical, free, browser-based calculators for electrical engineering, energy systems, and sustainability — built by a practicing engineer with 34+ years of experience. No login, no cost, no guesswork.
Real engineering formulas.
Instant, accurate results.
Every calculator on this platform uses established engineering methods — the same formulas applied on real projects. Each tool explains its inputs, assumptions, and the basis behind the result so you always know what it is doing and why.
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Click any card to open the calculator. More tools are added regularly — bookmark this page.
Battery Capacity & Sizing Calculator
Compute VAH capacity and AH battery rating for solar, UPS, and off-grid power systems. Accounts for load, backup time, DoD, inverter efficiency, and utilization factor.
Carbon Footprint Calculator
Estimate CO₂ equivalent emissions from electricity consumption, fuel use, vehicle travel, and flights using IPCC and IEA emission factors. Covers all major emission sources.
Power Factor Improvement Calculator
Calculate the exact KVAR capacitor bank rating needed to improve power factor in 3-phase systems. Returns both KVAR and microfarad values for delta connection.
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