Science and Engineering
Free science and engineering calculators for Ohm's law, force, density, energy, pressure, resistor colour codes and conversions.
27 tools
Ohm's Law Calculator
Solve voltage, current, resistance and power — enter any two.
Science and Engineering
Scientific Notation Converter
Convert numbers to and from scientific notation.
Science and Engineering
Speed Distance Time Calculator
Solve speed, distance or time — enter the two you know.
Science and Engineering
Force Calculator (F = ma)
Calculate force, mass or acceleration with Newton’s second law.
Science and Engineering
Density Calculator
Calculate density, mass or volume from the other two.
Science and Engineering
Energy Converter
Convert energy between joules, calories, kWh, BTU and more.
Science and Engineering
Pressure Converter
Convert pressure between Pa, bar, atm, psi, mmHg and more.
Science and Engineering
Feels-Like Temperature Calculator
Calculate the apparent temperature from wind chill or heat index.
Science and Engineering
Beaufort Wind Scale Calculator
Convert a wind speed to its Beaufort force number and description.
Science and Engineering
Resistor Color Code Calculator
Decode a 4-band resistor’s colour code into its resistance and tolerance.
Science and Engineering
Slope & Grade Calculator
Calculate slope as a percentage grade, angle and ratio from rise and run.
Science and Engineering
Molar Mass Calculator
Find the molar mass and percent composition of any chemical formula.
Science and Engineering
Kinetic & Potential Energy Calculator
Calculate kinetic energy (½mv²) or gravitational potential energy (mgh).
Science and Engineering
Projectile Motion Calculator
Find range, maximum height and time of flight for a projectile.
Science and Engineering
Molarity Calculator
Calculate the molarity of a solution from moles or mass and volume.
Science and Engineering
ABV Calculator
Calculate alcohol by volume (ABV) from original and final gravity.
Science and Engineering
Decibel Calculator
Convert ratios to decibels and combine multiple sound levels.
Science and Engineering
Wire Gauge (AWG) Calculator
Convert AWG to diameter, area and resistance.
Science and Engineering
BTU Calculator
Estimate the air-conditioner BTU needed to cool a room.
Science and Engineering
Voltage Drop Calculator
Calculate the voltage drop over a wire run.
Science and Engineering
Solar Panel Calculator
Estimate the solar system size and number of panels you need.
Science and Engineering
Battery Life Calculator
Estimate how long a battery lasts from its capacity (mAh) and the device current draw (mA).
Science and Engineering
Specific Heat Calculator
Solve Q = m·c·ΔT for heat energy, mass, specific heat or temperature change.
Science and Engineering
pH Calculator
Find pH, pOH and ion concentrations for a solution.
Science and Engineering
Pendulum Calculator
Find the period of a simple pendulum from its length, or the reverse.
Science and Engineering
Hooke's Law Calculator
Solve F = k·x for spring force, spring constant or displacement.
Science and Engineering
Tone Generator
Play a pure tone at any frequency from 20 Hz to 20 kHz.
Science and Engineering
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