Everyday Calculators
Everyday calculators for quick answers.
Percentage Calculator solves the three common percentage questions, Age Calculator turns a date of birth into an exact age, and Date Difference Calculator counts the days between two dates. Unit Converter covers length, weight, temperature, volume, area, and speed across 46 units using exact international definitions. For the conversions people look up most — cm to inches, kg to lbs, Celsius to Fahrenheit, miles to km, liters to gallons, square meters to square feet, and more — the dedicated converters work in both directions as you type, show the exact factor or formula, and include a table of common values.
All everyday calculators
Percentage Calculator
Solve all three percentage questions in one place — X% of Y, X as a percent of Y, and percent change — instantly, with the sentence spelled out.
Age Calculator
Turn a date of birth into an exact age in years, months, and days — plus total days lived and a countdown to the next birthday.
Date Difference Calculator
Count the days between two dates — total days, weeks plus days, and a calendar breakdown, with an option to include the end day.
Unit Converter
Convert length, weight, temperature, volume, area, and speed between 46 units using exact international definitions — instantly, with the formula shown.
CM to Inches Converter
Convert centimeters to inches (and back) with the exact 2.54 factor — instant results, a common-sizes table, and the height conversions people actually look up.
KG to LBS Converter
Convert kilograms to pounds (and back) using the exact 2.2046226 factor — body weight, luggage limits, and gym plates, converted instantly on your device.
Celsius to Fahrenheit Converter
Convert °C to °F (and back) with the exact formula — weather, fever, and oven temperatures instantly, plus the anchor points worth memorizing.
Miles to KM Converter
Convert miles to kilometers (and back) with the exact 1.609344 factor — road distances, running races, and speed limits, converted as you type.
Meters to Feet Converter
Convert meters to feet (and back) using the exact 0.3048 definition — ceilings, mountains, pools, and altitude, with a common-values table.
Grams to Ounces Converter
Convert grams to ounces (and back) with the exact 28.349523 factor — recipes, postage, and portions, plus the troy-ounce trap explained.
Liters to Gallons Converter
Convert liters to US gallons (and back) with the exact 3.785411784 definition — fuel, tanks, and aquariums, with the UK imperial gallon handled honestly.
MM to Inches Converter
Convert millimeters to inches (and back) with the exact 25.4 definition — plus the fraction table (1/16ths) that hardware and jewelry sizes actually use.
Feet to Meters Converter
Convert feet to meters (and back) using the exact 0.3048 definition — real estate, aviation altitudes, and sports distances, converted instantly.
KM/H to MPH Converter
Convert km/h to mph (and back) with the exact 1.609344 relationship — speed limits abroad, treadmill settings, and wind speeds, as you type.
Pounds to KG Converter
Convert pounds to kilograms instantly (and back) with the exact 0.45359237 definition — for metric medical forms, international shipping, and metric gyms.
Inches to CM Converter
Convert inches to centimeters instantly (and back) with the exact 2.54 definition — TV sizes, US product specs, and sewing measurements in metric.
Fahrenheit to Celsius Converter
Convert °F to °C instantly (and back) with the exact formula — US oven recipes, thermostat settings, and weather for metric readers.
KM to Miles Converter
Convert kilometers to miles instantly (and back) with the exact 0.62137119 factor — race distances, pace math, and rental-car odometers.
Stone to KG Converter
Convert stone to kilograms instantly (and back) — the exact 6.35029318 factor, plus stones-and-pounds arithmetic for UK body weight.
ML to OZ Converter
Convert milliliters to US fluid ounces instantly (and back) — the exact 29.5735 factor, the TSA 100 mL = 3.4 oz rule, and recipe liquid measures.
Square Meters to Square Feet Converter
Convert square meters to square feet instantly (and back) with the exact 10.7639 factor — apartment listings, offices, and why linear factors mislead.
Hectares to Acres Converter
Convert hectares to acres instantly (and back) with the exact 2.4710538 factor — farmland, plots, and how both units relate to football pitches.
MPH to KM/H Converter
Convert mph to km/h instantly (and back) with the exact 1.609344 factor — US speed limits for visiting drivers, hurricane categories, and ball speeds.
Yards to Meters Converter
Convert yards to meters instantly (and back) with the exact 0.9144 definition — golf distances, pool lengths, fabric, and football fields.