Skydiving & Parachute Calculator
Calculate freefall duration times, wing loading weights, canopy opening hard decks, and dropzone drift headings.
Configure Parameters
You can comfortably fly upwind with an estimated upwind ground speed of 13.0 mph.
Explore Additional Utilities
Anchor Scope Calculator
Calculate the recommended anchor rode chain and rope lengths based on water depth, vessel height, and environmental conditions.
Reverberation Time (RT60) Calculator
Estimate room RT60 reverberation times using Sabine and Eyring formulas, room volume, and surface absorption coefficients.
Eruption column height ↔ VEI — volcanic explosivity index
Correlate volcanic plume heights with Volcanic Explosivity Index (VEI) categories.
Yarn Weight Converter
Convert yarn sizes across WPI (Wraps Per Inch), ply, and standard weight categories.
Equatorial Coordinates Converter
Convert Right Ascension (RA) and Declination (Dec) to Hour Angle and Alt-Azimuth coordinates.
Body Surface Area (BSA) Calculator
Calculate body surface area (BSA) for clinical dosing using Mosteller, DuBois, Haycock, and Gehan-George formulas.
Stone size ↔ carat estimator
Estimate carat weight of round, oval, emerald, pear, or marquise cut gemstones from their physical dimensions and specific gravity.
Fabric Width Yardage Converter
Convert fabric yardage requirements between different standard widths like 44 inches and 60 inches.
VO2 Max & Aerobic Capacity Estimator
Convert running race times or heart rates into VO2 Max estimates and aerobic fitness classifications.
Mohs Hardness & Scratch Resistance
Compare minerals, absolute hardness values, and scratch interactions using the classic 1-10 Mohs scale and Knoop indentation hardness.
Paint Coverage Calculator
Estimate the gallons or liters of paint needed based on area and number of coats.
Earthquake Magnitude (Richter ↔ Moment)
Convert and compare earthquake energy release, shaking amplitude, and felt effects between Richter (ML) and Moment Magnitude (Mw) scales.
Dewpoint & Relative Humidity Calculator
Calculate dewpoint, relative humidity, or air temperature using the Magnus-Tetens formula.
Cloud Base Height Estimator
Estimate cloud condensation levels and cloud base height based on temperature and dewpoint spreads.
Sievert ↔ rem (Dose Equivalent)
Convert between Sieverts (Sv), rem, millisieverts (mSv), and millirem (mrem) to quantify biological effects and occupational radiation risk.
Wind power density — wind speed ↔ watts per sq meter
Calculate available wind kinetic power density (W/m²) based on wind speed and localized air density characteristics.
Horse Height (Hands ↔ cm ↔ inches)
Convert equestrian height from traditional hands (hh, where 1 hand = 4 inches) to centimeters and inches, with pony/horse classification.
Solar irradiance — W/m² ↔ peak sun hours
Convert solar irradiance (W/m²) and daylight duration to Peak Sun Hours (PSH) and estimate daily solar panel system output.
Watch beat rate — BPH ↔ Hz ↔ vibrations per hour
Convert mechanical watch balance wheel frequencies between Beats Per Hour (BPH), Vibrations Per Hour, and Hertz (Hz).
Animal Feed & Dry Matter Calculator
Convert animal body weight percentage dry matter intake (DMI) to daily feed requirements in kg/lbs, based on feed dry matter ratio and species presets.