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How to Use Unit Converter
Step 1
Choose unit type
Step 2
Enter your value
Step 3
Select target unit
Step 4
Copy result
What Is a Unit Converter?
A unit converter is an online tool that converts measurements between different units across categories like length, weight, temperature, volume, area, speed, and time. Instead of memorizing conversion factors or doing manual math, you enter a value and instantly see it in any other unit.
How to Convert Units Online
- Choose your unit type — length, weight, temperature, volume, etc.
- Enter your value in the source unit.
- Select the target unit you want to convert to.
- Copy the result and use it wherever you need.
Unit Categories Covered
Length: meters, kilometers, miles, feet, inches, centimeters, millimeters, yards, nautical miles
Weight/Mass: kilograms, grams, pounds, ounces, tonnes, stone
Temperature: Celsius, Fahrenheit, Kelvin
Volume: liters, milliliters, gallons, pints, cups, fluid ounces, cubic meters
Area: square meters, square feet, acres, hectares, square kilometers, square miles
Speed: km/h, mph, m/s, knots
Time: seconds, minutes, hours, days, weeks, months, years
Most Common Conversions
Miles to kilometers: 1 mile = 1.60934 km. Useful when reading US road distances in a metric country.
Pounds to kilograms: 1 lb = 0.453592 kg. Used in fitness, medical, and shipping contexts.
Fahrenheit to Celsius: °C = (°F – 32) × 5/9. Used by travelers between the US and the rest of the world.
Gallons to liters: 1 US gallon = 3.78541 liters. Commonly needed for fuel and cooking.
Metric vs Imperial
Most of the world uses the metric system (meters, kilograms, liters). The United States primarily uses the imperial system (feet, pounds, gallons). The UK uses a mix. Unit converters are essential for international communication, travel, e-commerce, and scientific work.
Frequently Asked Questions
What is the difference between US and UK gallons? A US liquid gallon is 3.785 liters; a UK imperial gallon is 4.546 liters. Always check which gallon is meant in recipes and fuel measurements.
How is temperature conversion different? Temperature conversions use formulas (not simple multiplication) because Celsius and Fahrenheit have different zero points.
Can I convert cooking measurements? Yes — the volume converter handles cups, tablespoons, teaspoons, fluid ounces, and milliliters used in recipes.