Math & Numbers
Linear and volumetric thermal expansion of an isotropic material. Linear: ΔL = α·L₀·ΔT, L₁ = L₀·(1+α·ΔT). Volumetric: ΔV = 3α·V₀·ΔT (β = 3α for isotropic solids). Built-in typical α for carbon/alloy steel, aluminum, copper, austenitic stainless, titanium and glass, plus custom. ΔT in K or °C, length in mm, volume in mm³.
thermal-expansion-calculatorMath & Numbers
Thermal stress in a fully constrained member under a uniform temperature change: σ_th = E·α·ΔT. Built-in typical Young's modulus E and expansion coefficient α for carbon/alloy steel, aluminum, copper, austenitic stainless and titanium, plus custom values. ΔT in K or °C (same magnitude), result in MPa. Heating (ΔT>0) → compressive stress in the member.
thermal-stress-calculatorMath & Numbers
Compute the thermal comfort indices PMV (Predicted Mean Vote, −3 cold..+3 hot) and PPD (Predicted Percentage Dissatisfied, %) per ISO 7730 / ASHRAE 55, using the Fanger equations. Inputs: air temperature Ta, mean radiant temperature Tr, relative air velocity v_ar, relative humidity φ, metabolic rate M (met; 1 met = 58.2 W/m²), clothing insulation Icl (clo; 1 clo = 0.155 m²·K/W), and external work W (defaults to 0). The clothing surface temperature Tcl is solved iteratively. Returns a 7-level ASHRAE sensation label.
thermal-comfort-pmvMath & Numbers
Calculate active, reactive, and apparent power for a balanced three-phase system: S=√3·U·I, P=√3·U·I·cosφ, Q=√3·U·I·sinφ. Also returns the power-factor angle φ and verifies the power triangle.
three-phase-power-calculatorMath & Numbers
Reflect an impedance through an ideal transformer: Z' = a²·Z, where a = N₁/N₂. Supports secondary→primary and primary→secondary directions; a can be given directly or derived from N₁/N₂. Also returns admittance Y and reflected admittance.
transformer-impedance-transferMath & Numbers
Ideal transformer ratio: a = N₁/N₂ = V₁/V₂ = I₂/I₁. Given turns, voltage, or current on either side, compute a and the corresponding voltage/current on the other side; verifies V₁·I₁ = V₂·I₂.
transformer-turns-ratioMath & Numbers
Convert common physical, chemistry, cooking, medical, and information units with the formula and dimensional analysis visible.
unit-converter-with-formulaFinance
Compare supermarket product prices by normalizing them to a common unit (per 100g, per liter, per piece, etc.). Enter products as 'name, price, quantity, unit' per line. Ranks from cheapest to most expensive per unit and shows savings vs the most expensive option.
unit-price-calculatorMath & Numbers
Compute torque, force, or lever arm from τ = r·F·sin(θ), with the perpendicular force component shown
torque-calculatorMath & Numbers
Calculate Gibbs free energy ΔG = ΔH − TΔS, reaction spontaneity, equilibrium temperature, and equilibrium constant K.
thermodynamics-gibbs-calculatorCalculator
Estimate how many tiles you need to cover a room, including layout-aware waste (straight, 45° diagonal, herringbone, basketweave), boxes to buy, grout volume and weight, and an optional cost total. Enter room and tile dimensions plus joint width to get a ready-to-order material list.
tile-coverage-estimatorCalculator
Enter a tire size (285/70R17), differential/final-drive ratio, and transmission gear ratios to compute the true overall tire diameter, circumference, revolutions per mile/km, an RPM × gear speed table, effective final drive after a tire change, and speedometer error. Metric or imperial units, with optional before/after tire comparison.
tire-gear-ratio-calculator