Unit Conversion Calculators
Convert between any units, length, weight, temperature, volume, pressure, speed, and 20 more dimensions. Bidirectional conversion with full precision. Includes both common and specialized units for engineering and science.
- ✓Common: length, weight, temperature, volume, area
- ✓Engineering: pressure, torque, force, flow rate, density
- ✓Digital: data storage, wire gauge, frequency
- ✓Specialty: cooking units, clothing sizes, shoe sizes, paper sizes
Most used: Temperature Converter, Length Converter, Weight Converter
Try any of the 25 unit conversion calculators below — or get one free for your AI.
Every calculator on this page is free to use right now. You can also download any one as a Claude skill file (free with email) to chat with it in Claude Code, ChatGPT, or any AI platform. Or get the full Unit Conversion Pack for $29.
Common workflows in this category
Click any scenario to jump into the calculator with the example pre-loaded.
25 free calculators
Angle Converter
Convert degrees to radians to gradians instantly. Free angle and rotation unit converter.
Area Converter
Convert acres to hectares, square feet to square meters. Free area and land measurement converter.
Clothing Size Converter
Convert clothing sizes between US, UK, EU, and Asian standards. Find your perfect fit when shopping internationally.
Hex/RGB Color Converter
Convert between hex codes, RGB values, and HSL color formats. Perfect for web design and color work.
Cooking Unit Converter
Convert cooking measurements between cups, tablespoons, teaspoons, and milliliters. Perfect recipe conversions every time.
Data Storage Converter
Convert MB to GB, GB to TB, KB to MB instantly. Free digital storage and file size converter.
Density Converter
Convert density between kg/m³, lb/ft³, g/cm³, and other units. For materials science, engineering, and chemistry work.
Energy Converter
Convert joules to calories to BTU to kilowatt-hours instantly. Free energy and work unit converter.
Flow Rate Converter
Convert flow rate between GPM, liters per minute, m³/hr, and other units. Essential for pumps, plumbing, and fluid systems.
Force Converter
Convert newtons, pounds-force, kilogram-force, and dynes. Essential for engineering, mechanics, and physics calculations.
Frequency Converter
Convert frequency between Hz, kHz, MHz, GHz, and other units. Essential for electronics, radio, and communications.
Fuel Economy Converter
Convert MPG to L/100km for international car comparisons. Free fuel efficiency and economy converter.
Length Converter
Convert inches to cm, feet to meters, miles to km. Use our free length converter for any distance measurement you need.
Number to Words Converter
Convert numbers to words for checks, legal documents, and contracts. Handles decimals and large numbers accurately.
Paper Size Converter
Convert between A4, US Letter, Legal, A3, and all paper sizes. See exact dimensions in inches and millimeters.
Power Converter
Convert watts to horsepower to BTU/hr instantly. Free power and mechanical force unit converter.
Pressure Converter
Convert PSI to bar to pascal to atm to mmHg instantly. Free pressure and atmospheric unit converter.
Shoe Size Converter
Convert shoe sizes between US, UK, EU, Japan, and international standards. Find your exact size in any country.
Speed Converter
Convert mph to km/h, m/s to knots instantly. Free speed and velocity converter for travel and driving.
Temperature Converter
Convert Fahrenheit to Celsius to Kelvin instantly. Free temperature unit converter for any climate, weather, or scientific data.
Time Unit Converter
Convert seconds to minutes to hours to days to years instantly. Free time measurement converter.
Torque Converter
Convert newton-meters to foot-pounds, kilogram-meters, and inch-pounds. Essential for mechanics, engineers, and auto repair.
Volume Converter
Convert gallons to liters, cups to ml, fluid ounces to cubic inches. Free volume unit converter for cooking and measurements.
Weight Converter
Convert pounds to kg, ounces to grams, stones to lbs. Free weight and mass converter for any measurement.
Wire Gauge Converter
Convert wire gauge between AWG, mm², mm diameter, and other units. Essential for electrical work and electronics.