Unit Converter

Unit conversion is the process of converting values between different measurement systems, essential in science, engineering, and everyday life. Conversion between the metric system (SI units) and imperial system (US customary units) is most common. Accurate unit conversion is crucial for international trade, scientific research, and daily calculations.

Length: 1 inch = 2.54 cm, 1 foot = 30.48 cm, 1 mile = 1.60934 km
Weight: 1 pound = 453.592 g, 1 kilogram = 2.20462 pounds
Temperature: °F = (°C × 9/5) + 32, °C = (°F - 32) × 5/9
Volume: 1 gallon (US) = 3.78541 L, 1 liter = 0.264172 gallon
Speed: 1 m/s = 3.6 km/h = 2.23694 mph
Data: 1 KB = 1,024 bytes, 1 MB = 1,024 KB

The metric system was created during the French Revolution in the 1790s based on decimal system, and the International System of Units (SI) was officially adopted in 1960. The imperial system is primarily used in the United States, with common units like inches, feet, pounds, and gallons. Most countries have officially adopted the metric system, but the US continues to primarily use imperial units.

Celsius (°C): Water freezes at 0°C, boils at 100°C, used in most countries
Fahrenheit (°F): Water freezes at 32°F, boils at 212°F, mainly used in US
Kelvin (K): Absolute zero at 0K = -273.15°C, used in scientific fields

In daily life, 20°C (68°F) is considered a comfortable room temperature.

Cooking: Convert recipe cups to grams
Shopping: Convert screen sizes from inches to centimeters
Driving: Convert miles to kilometers
Real Estate: Calculate square feet to square meters
Weather: Convert Fahrenheit to Celsius for temperature
Body Weight: Convert pounds to kilograms

In scientific experiments, medication dosage, and architectural design, accurate unit conversion is directly linked to life and safety. NASA's Mars Climate Orbiter failed in 1999 due to calculation errors from mixing metric and imperial units. In aviation, medical, and construction fields, standardized unit usage and double-checking are essential.