Origami Scaling & SizingOrigami & Folding
Calculate required starting square paper size to achieve a specific target finished 3D model size for standard designs (e.g., Crane, Box, Kawasaki Rose, Dragon).
Origami is the intersection of mathematical geometry and material engineering. Optimal folds are highly dependent on fiber lengths and wood grain direction.
Simple fold. Wingspan is approx. 50% of starting square diagonal.
Explore Additional Utilities
pH adjustment — acid/alkali drops ↔ pH change estimate
Estimate acidifying or alkalizing solution amounts to safely adjust formulation pH values.
R-value ↔ U-value — insulation thermal resistance
Convert between R-value thermal resistance and U-value heat transmittance with preset materials lookup.
Currency Converter
Convert global currencies using simulated or fetched live rates (USD, EUR, GBP, JPY, etc.).
Ocean depth ↔ pressure — bar per 10 meters rule
Calculate hydrostatic and total pressure in the ocean based on depth, water density, and gravity constants.
Drug Concentration Converter
Convert pharmaceutical concentrations between % w/v, mg/mL, and mol/L using substance molecular weight presets.
Electrode size ↔ amperage range — stick welding
Match stick electrode sizes (3/32", 1/8", 5/32") and classes (E7018, E6010, E6013) with optimal welding amperage ranges.
International Ring Size Matcher
Compare finger size rings across US, UK, Europe, and Asian dimensions.
Responsive Font Units Converter
Compute points, pixels, em, rem web font guidelines, and equivalent font sizes.
Ballistic Mils ↔ Angles
Convert between ballistics mils (NATO, Warsaw, Swedish), degrees, and MOA, with range estimation calculators.
Numerical aperture ↔ acceptance angle — fiber coupling
Determine light coupling capabilities, supported modes, V-numbers, and acceptance cone widths for optical optical fibers.
Scientific Temperature Scale
Convert scientific scales between Celsius, Fahrenheit, Kelvin, and Rankine thermal indicators.
Soil Permeability Converter
Convert coefficient of permeability (hydraulic conductivity) between cm/s, m/day, ft/day, and m/s with soil type drainage classifications.
Board size — rider weight ↔ wind conditions → liters
Calculate optimal board size, volume, and dimensions for your riding style.
Wave height ↔ wave period — sea state description
Assess Significant Wave Height, period, WMO sea states, wave wavelength, celerity speed, and steepness limits.
Heat flux — watts per square meter ↔ BTU/hr·ft²
Convert heat transfer rates per unit area between W/m², kW/m², BTU/hr·ft², and cal/s·cm².
Water resistance — ATM ↔ bar ↔ meters depth rating
Convert water pressure tolerances across ATM, Bar, and depth meters. Understand safe real-world water sport activities.
Tank turnover rate — volume ↔ pump flow → exchanges per hour
Determine water exchange rate per hour and cycle duration based on tank volume and pump flow rate specifications.
Mortality Rate & Life Expectancy
Explore actuarial cohort metrics, Gompertz-Makeham mortality rates, survival probabilities, and remaining life expectancy by age.
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.
Species-Specific Drug Dosing
Calculate animal weight-based dosages, target mg requirements, and liquid volumes across different species: dogs, cats, horses, cattle, and rabbits.