Science calculators

Science calculators for physics, chemistry, electronics, and engineering. Correct SI units, referenced formulas, and worked examples throughout.

18 calculators

  • Capacitor Energy Calculator

    Enter any two of capacitance, voltage and stored energy — the calculator returns the third using E = ½ C V², and also reports the charge Q = C·V on the plates.

  • Dew Point Calculator

    Enter the current air temperature and relative humidity. The calculator returns the dew point — the temperature at which the air would have to cool for water to start condensing — plus the temperature–dew-point spread and a perceived-comfort band.

  • Dilution Calculator (C₁V₁ = C₂V₂)

    Work out how much stock to take, how much solvent to add, or what concentration you will end up at when diluting a solution. Solves any of the four variables in C₁V₁ = C₂V₂.

  • Engine Horsepower Calculator

    Compute engine horsepower three ways: from a dyno torque curve (HP = T × RPM / 5252), from quarter-mile trap speed (Huntington method), and from quarter-mile elapsed time (Patrick Hale method).

  • Force Calculator

    Enter any two of force, mass and acceleration — the calculator returns the third using Newton’s second law, F = m·a, and converts the force into common units.

  • Half-Life Calculator

    Solve any of N₀, N(t), t, or T from the other three using the standard decay equation N(t) = N₀ × (½)^(t/T). Works for radioactive isotopes, first-order chemical reactions, and drug elimination — any process with a constant half-life.

  • Heat Index Calculator

    Enter the air temperature and relative humidity. The calculator returns the heat index — what hot, humid air actually feels like on exposed skin — using the National Weather Service Rothfusz regression, plus an NWS heat-risk band.

  • Mass Calculator

    Enter density and volume in your preferred units. The calculator returns the mass in kilograms, grams, pounds and ounces using m = ρ · V.

  • Molarity Calculator

    Compute the molarity of a solution, the mass of solute needed for a target concentration, or the volume to make from a given amount — all from M = n/V with n = mass/MW.

  • Molecular Weight Calculator

    Type a chemical formula and get the molar mass in g/mol, with each element’s mass contribution and percentage.

  • Ohm's Law Calculator

    Enter any two of voltage (V), current (I), resistance (R) or power (P). The calculator returns the other two using Ohm's law and the DC power equations.

  • pH Calculator

    Enter any one of [H⁺], [OH⁻], pH or pOH — the calculator returns the other three at 25 °C, plus an acid/base classification.

  • Resistor Color Code Calculator

    Pick the four band colours and read out the resistance in ohms, kilo-ohms or mega-ohms — with the tolerance min/max range — using the IEC 60062 colour code.

  • Voltage Drop Calculator

    Calculate voltage drop across a copper or aluminum branch circuit or feeder. Uses NEC Chapter 9 Table 8 DC resistance at 75 °C and flags whether the run meets the NEC-recommended ≤ 3 % branch-circuit limit.

  • Wavelength Calculator

    Enter any two of wavelength, frequency and wave speed — the calculator returns the third using the universal wave relation v = f·λ, with results converted into the SI prefixes that make sense at that scale.

  • Wind Chill Calculator

    Enter the air temperature and wind speed. The calculator returns the wind chill — what the cold actually feels like on exposed skin — using the National Weather Service and Environment Canada formula, plus a frostbite risk band.

  • Wire Gauge Calculator

    Look up the ampacity, diameter, cross-section, and DC resistance of an American Wire Gauge conductor. Covers 14 AWG to 4/0 in copper and aluminum at 60, 75, and 90 °C insulation ratings, with the NEC Table 310.16 ampacity and the NEC 240.4(D) small-conductor overcurrent cap applied automatically.

  • Young's Modulus Calculator

    Enter the axial force, cross-sectional area, original length and elongation of a specimen. The calculator returns stress σ, strain ε and Young's modulus E.