Instant answers with real-time (AJAX) updates
Most popular calculators
Avogadro’s number calculator
Calculate moles, particles, mass and molar mass using Avogadro’s constant. Real-time results with unit selectors and PDF export; mobile-friendly.
BC ⇄ AD Year Difference Calculator
Quickly calculate time between BC and AD years. No year zero rule built-in, with steps, tips, and one-click PDF.
Beam Deflection Calculator
Free beam deflection calculator for simply supported & cantilever beams. Point, uniform & triangular loads; set E/I or EI; instant results with steps & PDF.
Body Shape Calculator
Use our free body shape calculator to find your body type from bust, waist, high hip and hip plus waist–hip ratio. Quick, visual and easy.
Face Shape Calculator
Free face shape calculator using forehead, cheekbones, jawline and face length to classify your face as oval, round, square, heart or diamond.
Grams To Calories Calculator
Convert grams of carbs, protein, fat, and alcohol to calories (kcal) instantly. Live unit syncing, steps, tips, and PDF export.
Helium Balloons Calculator
Calculate how many helium balloons you need for any weight, plus lift per balloon and helium volume, with this easy online calculator.
IQ PERCENTILE CALCULATOR
Calculate your IQ percentile using μ=100 and σ=15 or 16. See percentile plus percent above and below instantly with live results.
mg to mL Calculator
Convert mg to mL and back using density or medication concentration. Live syncing, step-by-step guide, and PDF export. Free at Ajax Calculator.
Punnett Square Calculator
Use our Punnett Square Calculator to model a monohybrid cross, see AA/Aa/aa probabilities, genotypic & phenotypic ratios, and download a PDF of the results.
RPM Calculator
Calculate engine RPM, speed, gear ratio & tire diameter with real-time results and unit conversions. Free, fast, mobile-friendly RPM calculator.
Waist-to-Height Ratio (WHtR) Calculator
Free waist-to-height ratio calculator. Enter your height and waist in cm or inches to get WHtR, health risk category, and simple interpretation.