What types of units can I convert with this tool?

The converter supports all common measurement categories: length (meters, feet, miles, kilometers, inches, centimeters, yards, millimeters), weight/mass (kilograms, pounds, ounces, grams, tons, milligrams), temperature (Celsius, Fahrenheit, Kelvin), volume (liters, gallons, milliliters, cups, pints, quarts, fluid ounces), area (square meters, square feet, acres, hectares, square kilometers, square miles), speed (miles per hour, kilometers per hour, meters per second, knots), time (seconds, minutes, hours, days, weeks, years), energy (joules, calories, kilowatt-hours), pressure (pascals, PSI, bar, atmospheres), and data storage (bytes, kilobytes, megabytes, gigabytes, terabytes). Each category includes both metric (SI) and imperial/US customary units for comprehensive conversion support.

How do I convert common measurements like miles to kilometers?

Select the 'Length' category, choose 'Miles' as the source unit, enter your value (e.g., 10), then select 'Kilometers' as the target unit. The converter instantly shows the result (10 miles = 16.09344 kilometers). Common conversions work the same way: for pounds to kilograms, use 'Weight' category with lb to kg (1 lb = 0.453592 kg). For Celsius to Fahrenheit, use 'Temperature' with °C to °F (0°C = 32°F, 100°C = 212°F). The tool uses exact conversion factors for precision—no approximations. Bookmarking frequently used conversions or using the converter's history (if available) speeds up repeated conversions. All calculations happen instantly in your browser with results updating as you type for real-time feedback.

How precise are the unit conversions?

Conversions use exact mathematical factors defined by international standards. For example, 1 inch = exactly 25.4 millimeters, 1 pound = exactly 0.45359237 kilograms, 1 mile = exactly 1.609344 kilometers. These factors ensure scientific accuracy. Results display up to 10 decimal places for precision, though practical use rarely needs more than 2-4 decimals. For temperature conversions, formulas are exact: °F = (°C × 9/5) + 32, K = °C + 273.15. Rounding errors are negligible—conversions are accurate within the limits of floating-point arithmetic (approximately 15-17 significant digits). For engineering, scientific, or legal applications requiring extreme precision, these conversions meet professional standards. Cooking or everyday conversions only need 1-2 decimal places.

Can I convert between metric and imperial systems easily?

Yes! The converter is specifically designed for metric-imperial conversions. Select any metric unit (meters, kilograms, Celsius, liters) and convert to its imperial equivalent (feet, pounds, Fahrenheit, gallons) or vice versa. Common examples: 1 meter = 3.28084 feet, 1 kilogram = 2.20462 pounds, 0°C = 32°F, 1 liter = 0.264172 gallons. This is essential for international communication, travel (speed limits in mph vs km/h), cooking (recipes in cups vs milliliters), construction (inches vs centimeters), and science (where metric is standard). The tool handles both systems equally—no preference or default. For countries using mixed systems (like the US and UK), this converter eliminates confusion and ensures accurate measurements across different unit conventions.

How do I convert cooking measurements like cups to milliliters?

Select 'Volume' category, choose 'Cups' (US customary) as source unit, enter your recipe amount, and convert to 'Milliliters.' Standard conversions: 1 US cup = 236.588 mL (about 240 mL for practical cooking), 1 tablespoon = 14.787 mL (about 15 mL), 1 teaspoon = 4.929 mL (about 5 mL), 1 fluid ounce = 29.574 mL (about 30 mL), 1 gallon = 3785.41 mL = 3.785 liters. Be aware that US cups differ from metric cups (250 mL) and UK imperial cups (284 mL). For dry ingredients, weight conversions are more accurate than volume—1 cup of flour weighs differently than 1 cup of sugar. When converting recipes, round to practical measurements: 236 mL becomes 240 mL, 473 mL becomes 500 mL (2 cups = 500 mL works for most recipes).

Are scientific and engineering units supported?

Absolutely! The converter includes scientific units beyond everyday measurements: energy (joules, ergs, BTU, electron volts), power (watts, horsepower, BTU per hour), pressure (pascals, bar, torr, mmHg, atmospheres, PSI), force (newtons, dynes, pounds-force), frequency (hertz, kilohertz, megahertz, gigahertz), digital storage (bits, bytes, kilobytes using both 1000-based SI and 1024-based binary), radiation (becquerels, curies), luminance (candelas, lumens, lux), and angular measurements (degrees, radians, gradians). These are essential for physics, chemistry, engineering, computer science, and technical fields. Conversion factors follow international standards (SI units). For specialized fields, the converter provides accurate conversions between related units—e.g., converting horsepower to watts or atmospheres to pascals.

Can I batch convert multiple values at once?

Most basic unit converters process one value at a time—enter a number, get the converted result. For batch conversion (converting multiple values simultaneously), you'd need to repeat the process for each value or use spreadsheet software (Excel, Google Sheets) with formulas. Some advanced converters offer batch mode where you paste a list of values and get converted results in bulk. Alternatively, once you set up a conversion (e.g., miles to kilometers), changing only the input value updates the output instantly, making sequential conversions fast. For programming or automation needs, conversion formulas can be scripted (e.g., km = miles × 1.609344) and applied to datasets. Browser-based tools prioritize simplicity for individual conversions; desktop tools or scripts handle bulk conversion more efficiently.

How do temperature conversions work differently from other units?

Temperature conversions use formulas rather than simple multiplication because temperature scales have different zero points and intervals. Celsius to Fahrenheit: °F = (°C × 9/5) + 32 (e.g., 20°C = 68°F). Fahrenheit to Celsius: °C = (°F - 32) × 5/9 (e.g., 68°F = 20°C). Celsius to Kelvin: K = °C + 273.15 (e.g., 20°C = 293.15K). Kelvin is absolute temperature (0K = absolute zero, -273.15°C). These conversions account for scale offset (Fahrenheit's freezing point is 32°, not 0°) and different interval sizes (1°C = 1.8°F). Unlike length or weight where 0 feet = 0 meters, 0°C ≠ 0°F. This makes temperature conversions unique and requires understanding the relationship between scales, not just a conversion factor.

Can I convert between different systems like foot-pound-second (FPS) and SI?

Yes! The converter supports conversions between various unit systems: metric (SI), imperial (British), US customary, CGS (centimeter-gram-second), and FPS (foot-pound-second). For example, converting force from FPS (pounds-force) to SI (newtons): 1 lbf = 4.44822 N. Or energy from FPS (foot-pounds) to SI (joules): 1 ft-lb = 1.35582 J. This is crucial for engineering fields where different regions or industries use different standards—aerospace often uses FPS, science uses SI, construction varies by country. The converter handles these system differences transparently. Select your source unit system, enter the value, choose the target system, and get the converted result. Understanding these conversions prevents costly errors in international projects or scientific collaborations where unit system mismatches cause problems.

What should I know about converting historical or obsolete units?

Historical units like cubits (ancient measure, roughly 18 inches or 45 cm), leagues (about 3 miles or 4.8 km), stones (British weight, 14 pounds or 6.35 kg), rods (16.5 feet or 5.03 meters), furlongs (660 feet or 201 meters), and nautical miles (1852 meters) have varying definitions depending on era and region. Some converters include these for historical reference or specific use cases (nautical miles for maritime/aviation). Converting these requires knowing which definition is relevant—a Roman cubit differs from an Egyptian cubit. For practical purposes, stick to modern standardized units (metric or imperial). If working with historical documents or literature, research the specific definition used in that context. Modern unit converters that include historical units typically use widely accepted standard definitions, but note that precision may be less critical for archival or educational purposes than for engineering applications.

Unit Converter

Convert between units of length, weight, temperature, volume, area, speed, and more. Instant conversions with precise calculations—miles to kilometers, pounds to kilograms, Celsius to Fahrenheit.

Length Converter

Convert between different length units

From

Value

Converted Value