DPI / PPI Converter
Convert image pixel dimensions into physical print sizes (inches/cm) at any target resolution.
Explore Additional Utilities
Thermohaline density — temperature + salinity → seawater density
Determine seawater density and specific volume from water temperature and salinity using the UNESCO International Equation of State.
Void Fill Material Volume
Calculate empty space volume inside a shipping box after placing items to determine packaging material needed.
Flesch-Kincaid Reading Level
Calculate readability scores and Flesch-Kincaid school grade levels for any input text in real-time.
Board size — rider weight ↔ wind conditions → liters
Calculate optimal board size, volume, and dimensions for your riding style.
Soil Compaction Ratio Calculator
Calculate and convert soil compaction ratio, loose volume, compacted volume, and shrink/swell factor for cut-and-fill operations.
Dye concentration — wax weight ↔ color chips needed
Determine dry color chips or fluid dye drops needed based on total wax weight and target color depth.
One Rep Max (1RM) Calculator
Estimate your single repetition maximum lifting capacity (1RM) using major clinical lifting models (Epley, Brzycki, Lander).
Cosmic Distance Converter
Convert huge distances across Light Years, Parsecs, Astronomical Units, and Kilometers.
Mohs Hardness & Scratch Resistance
Compare minerals, absolute hardness values, and scratch interactions using the classic 1-10 Mohs scale and Knoop indentation hardness.
Oxygen Saturation & PaO2 Converter
Convert blood oxygen saturation (SpO2) to partial pressure of oxygen (PaO2) using the clinical Severinghaus-Ellis model.
Muzzle velocity — fps ↔ m/s ↔ km/h
Convert velocities between fps, m/s, and km/h. Calculate muzzle kinetic energy in Joules and Foot-Pounds.
Equatorial Coordinates Converter
Convert Right Ascension (RA) and Declination (Dec) to Hour Angle and Alt-Azimuth coordinates.
Soil Plasticity Index Calculator
Calculate Plasticity Index (PI) from Liquid Limit (LL) and Plastic Limit (PL), and interpret soil state using the Atterberg limits chart.
True wind ↔ apparent wind
Calculate apparent wind speed and angle from true wind speed, sailing angle, and boat speed (or vice versa).
IV Drip Rate (Drops/min ↔ mL/hour)
Convert IV flow rates between mL/hour and drops/minute (gtt/min) for any drop factor, with real-time dripping rate animation.
Thread Weight Converter
Convert between different thread sizing standards including Tex, Denier, and Number English (Ne).
Solar Panel Output & Yield Calculator
Calculate daily and annual electricity generation (kWh) based on solar panel capacity (kWp), peak sun hours, and system efficiency losses.
Stepper motor steps (degrees ↔ steps ↔ microsteps)
Convert between motor rotation angles in degrees, physical steps, and microsteps based on step angle and microstepping resolution.
Crown position ↔ function — hand setting vs winding
Map out the mechanical state and winding functions of crowns at positions 0, 1, and 2, including quickset dates and hacking.
Wind Turbine Power Generator
Estimate power output (watts) of a wind turbine based on wind speed, rotor diameter, blade sweep area, and aerodynamic power coefficients.