Paper Size Converter & Comparer
Calculate dimensions for A4, Letter, Legal and more in mm & inches, and visually compare overlapping standard sheets.
Global standard for business documents, letters, and printing.
Corporate standard in United States and Canada.
A4 Standard
US Letter
Explore Additional Utilities
Void Fill Material Volume
Calculate empty space volume inside a shipping box after placing items to determine packaging material needed.
Shoe Size Converter
Convert footwear sizes across US, UK, Europe, and Japanese standards for men and women.
Standing timber volume — DBH + height → cubic meters
Calculate merchantable standing timber volume in cubic meters or board feet using Doyle, Scribner, or International rules.
Hold size ↔ finger force — crimp load estimation
Estimate skeletal finger force and crimp tendon pulley loads (A2/A4) based on edge/hold size (mm) and climber weight.
Clinical Blood Pressure Gauges
Compare clinical medical blood pressure or vacuum values between mmHg and kPa units.
Electricity Billing (kWh ↔ MJ)
Analyze electric billing kilowatt-hours and physical energy auditing megajoule metrics.
DPI Screen Density Sizing
Calculate typographic sizing differences across varying screen device densities and target DPI scopes.
Gelatin & Agar Agar Converter
Convert between gelatin sheets (platinum, gold, silver, bronze), powdered gelatin, and vegan agar agar.
Displacement tonnage ↔ cubic meters — ship buoyancy
Convert ship displacement tonnage to submerged volume (m³) and buoyancy force. Choose between freshwater and saltwater standards.
Lumber Size & Board Feet Calculator
Calculate board feet volume, convert between nominal and actual lumber sizes, and estimate weights.
NATO Phonetic Alphabet
Spell out commands or names phonetically using the standard military/aviation phonetic alphabet.
Mechanical Power (W ↔ hp)
Convert physical engine horsepower ratings, mechanical draft forces, and electric wattages.
Data Storage Units
Convert digital storage capacity sizes across bits, Bytes, MB, GB, and Terabytes.
Lactate threshold — heart rate % ↔ training zone
Convert heart rate threshold percentages into targeted cardiovascular athletic training zones.
Entropy bits ↔ password strength — character set + length
Calculate Shannon entropy bits based on character pool variety and length. Estimate brute-force resistance across various threat models.
Column Grid Sizer
Calculate layouts, column widths, gutters, and page grids in picas, mm, or inches.
Length Converter
Convert between meter, kilometer, centimeter, mile, yard, foot, inch, and more.
Carton CBM ↔ Container Capacity
Convert carton dimensions to Cubic Meters (CBM) and calculate carton capacity for 20ft and 40ft shipping containers.
APR ↔ APY Yield Converter
Convert interest rates between Annual Percentage Rate (APR) and Annual Percentage Yield (APY).
Hijri ↔ Gregorian Calendar
Convert between Islamic Hijri calendar and standard Gregorian dates, with customized crescent visibility observation adjustments.