Science & Engineering Calculators

Science and Engineering Calculators for Electrical, Mechanical, Energy and Materials Work

Use these free science and engineering calculators to convert electrical units, estimate power and energy, check Ohm’s law, calculate solar panels, and work with pressure, force, torque, flow, speed, frequency, wavelength, density, and illumination.

Browse Science & Engineering Tools by Topic

Electrical and Power

Convert circuit units, estimate electricity costs, and check common electrical relationships.

Motion and Mechanics

Use these converters for speed, force, torque, angular acceleration, flow, and frequency.

Energy, Light and Materials

Convert units for energy, energy density, pressure, density, illumination, and wavelength.

Solar and Practical Engineering

Estimate solar panel output and connect technical calculations with real electricity use.

How to Use Technical Calculators Carefully

Start by identifying the physical quantity: power, energy, force, pressure, speed, torque, current, voltage, or frequency.
Confirm the unit symbols before converting. For example, W, kW, kWh, V, A, Pa, bar, psi, N, l/min, Hz, and rpm are not interchangeable.
Keep enough significant digits during the calculation, then round the final answer for the real-world task.
For engineering, electrical, medical, or safety-critical work, verify results against official standards, datasheets, and qualified professional guidance.

Tip: pair Science & Engineering tools with the Unit Converters hub when you need broader measurement conversions across metric, imperial, and technical unit systems.

Science & Engineering Calculators FAQ

Are these science calculators free?

Yes. These science and engineering calculators are free to use directly in the browser.

Can I use these calculators for engineering work?

You can use them for quick checks and planning, but safety-critical engineering work should be verified with official standards, calibrated tools, and qualified professionals.

Which calculator should I use for electricity cost?

Use the Electricity Cost Calculator when you know power use in watts or kilowatts and need to estimate cost from usage time and electricity price.

What is the difference between power and energy?

Power is a rate of using or producing energy, such as watts or kilowatts. Energy is the total amount used or produced, such as joules or kilowatt-hours.

Why do unit symbols matter so much?

Small symbol differences can represent different physical quantities. For example, kW and kWh are related but not the same, and confusing them can create large errors.