Real-World Use Cases

A runner in London training for a 10K race finds a training plan written in miles. Converting 6.2 miles to kilometers (9.98 km) lets them map the route on their local running app, which uses metric distances. The converter handles this instantly without needing to remember that 1 mile equals 1.60934 kilometers.

A home cook in New York following a British recipe needs to convert 200 grams of flour to cups. The recipe uses metric weight, but their kitchen scale is broken and they only have measuring cups. Converting 200 grams to ounces (7.05 oz) and then to cups (about 1.6 cups) saves the dish.

An engineer in Munich reviewing a US specification sheet encounters dimensions in inches and temperatures in Fahrenheit. Converting 0.25 inches to millimeters (6.35 mm) and 350 degrees Fahrenheit to Celsius (176.7 C) lets them verify the part fits their metric design and the operating temperature is within spec.

A student in Mumbai studying for a physics exam needs to convert 72 kilometers per hour to meters per second for a velocity problem. The converter gives 20 m/s instantly, saving time on unit conversion so they can focus on the actual physics calculation.

A traveler in Tokyo buying a 64GB phone wants to know how many photos that holds. Converting 64 gigabytes to megabytes (65,536 MB) and then estimating 3 MB per photo gives them a rough capacity of about 21,800 photos. The converter handles the data unit conversion accurately.

How It Works

The converter uses the Convert library, a TypeScript-native unit conversion library with zero dependencies. It supports over 50 unit categories including length, mass, temperature, volume, area, speed, data storage, pressure, energy, and more. All conversions use precise conversion factors defined by international standards.

Temperature conversions use offset formulas rather than simple multiplication. Celsius to Fahrenheit uses the formula F = C * 9/5 + 32. Fahrenheit to Celsius uses C = (F - 32) * 5/9. Kelvin conversions add or subtract 273.15. These offset conversions are handled automatically.

The 'Convert all' mode shows your input value converted to every unit in the selected category simultaneously. This is useful when you are not sure which unit you need and want to see all options at once. For example, entering 1 kilometer in length mode shows 1000 meters, 0.621 miles, 3281 feet, 1094 yards, and more.

For most categories, conversions are exact because they use defined conversion factors. For example, 1 inch is defined as exactly 25.4 millimeters. Temperature is also exact because the formulas are definitional. Some conversions involving historical or regional units may use approximate factors.

Step-by-Step Usage Guide

  1. Select a category from the tabs at the top (Length, Mass, Temperature, Volume, Area, Speed, Data, Pressure, Energy).
  2. Enter the value you want to convert in the input field.
  3. Select the source unit (the unit your value is currently in) from the 'From' dropdown.
  4. Select the target unit (the unit you want to convert to) from the 'To' dropdown.
  5. Read the converted result in the output field. The result updates instantly as you type or change units.
  6. Click 'Convert all' to see your input value in every unit of the selected category at once.
  7. Use the copy button to copy the result to your clipboard for use in other applications.

Examples

Input

5 kilometers to miles

Output

3.107 miles

1 kilometer = 0.621371 miles; useful for race distances and travel

Input

100 degrees Fahrenheit to Celsius

Output

37.78 C

Body temperature is about 98.6 F, which equals 37 C

Input

2 kilograms to pounds

Output

4.409 pounds

1 kilogram = 2.20462 pounds; common in cooking and shipping

Input

1 gallon (US) to liters

Output

3.785 liters

US liquid gallon; the imperial gallon (UK) is 4.546 liters

Input

50 megabytes to gigabytes

Output

0.0488 GB

Uses binary conversion: 1024 MB = 1 GB

Input

100 kilometers per hour to miles per hour

Output

62.14 mph

Highway speed limit conversion; 100 km/h is common in Europe

Common Mistakes and Edge Cases

Things to watch out for

  • US vs imperial liquid measures: A US gallon is 3.785 liters, but an imperial (UK) gallon is 4.546 liters. The converter uses US liquid measures by default. If you are working with UK recipes or fuel economy, check which gallon is being used.
  • Mass vs weight: Kilograms and grams are units of mass, while pounds are technically units of force (weight). In everyday use, pounds are treated as mass. The converter follows this convention. For precise scientific work, use newtons for force and kilograms for mass.
  • Temperature has no zero point in Fahrenheit and Celsius: 0 C and 0 F are arbitrary reference points, not true zeros. This means you cannot use ratios with these scales (20 C is not 'twice as hot' as 10 C). Only Kelvin has a true zero (absolute zero).
  • Binary vs decimal data units: Computer storage uses binary prefixes (1 KB = 1024 bytes) while storage manufacturers use decimal prefixes (1 KB = 1000 bytes). The converter uses binary conventions (1024). A 500 GB hard drive actually stores about 465 GiB.
  • Square vs cubic units: Area units (square meters, square feet) and volume units (cubic meters, cubic feet) are different categories. Converting square meters to cubic meters is not possible without a height dimension. Make sure you are using the correct category.
  • Significant figures: The converter shows results with high precision, but your input may not warrant that precision. If you enter 2 inches and get 50.8 millimeters, the result is exact because 1 inch is defined as exactly 25.4 mm. But if you enter 2.0 miles and get 3.21868 kilometers, the extra digits may not be meaningful.

FAQ

What units can I convert?

The converter supports length (meters, kilometers, miles, feet, inches, yards, nautical miles, and more), mass (kilograms, grams, pounds, ounces, tons, tonnes), temperature (Celsius, Fahrenheit, Kelvin), volume (liters, gallons, cups, pints, milliliters), area (square meters, acres, hectares, square feet), speed (km/h, mph, m/s, knots), data storage (bytes, kilobytes, megabytes, gigabytes, terabytes), pressure (pascals, bar, psi, atmospheres), and energy (joules, calories, watt-hours, BTUs).

How accurate are the conversions?

All conversions use internationally defined conversion factors. For example, 1 inch is exactly 25.4 millimeters, 1 pound is exactly 0.45359237 kilograms, and 1 gallon (US liquid) is exactly 3.785411784 liters. Temperature conversions use exact formulas. Results are accurate to the full precision of the conversion factor used.

What is the difference between US and imperial units?

US customary units and British imperial units share the same names but have different values for some measures. For example, a US gallon is 3.785 liters while an imperial gallon is 4.546 liters. A US pint is 473 ml while an imperial pint is 568 ml. The converter uses US customary units by default for liquid measures.

Can I convert temperature?

Yes. The converter handles Celsius, Fahrenheit, and Kelvin. Temperature conversions use offset formulas, not simple multiplication. For example, 0 C equals 32 F equals 273.15 K. The converter applies the correct formula automatically based on which units you select.

Why does my hard drive show less capacity than advertised?

Storage manufacturers use decimal units (1 GB = 1,000,000,000 bytes) while operating systems use binary units (1 GiB = 1,073,741,824 bytes). A 500 GB drive shows as about 465 GiB in your operating system. The converter uses binary conventions (1024-based) for data units, which matches what your computer reports.

Can I convert between different categories?

No. You can only convert within a category (length to length, mass to mass, etc.). You cannot convert kilometers to kilograms because they measure different physical quantities. If you need to convert area to volume, you need an additional dimension (height or depth) that the unit converter cannot provide.

Does the converter work offline?

Yes. All conversions are calculated client-side in your browser using the Convert JavaScript library. No internet connection is needed after the page loads. The conversion factors are built into the library and do not change.

What is a nautical mile and how is it different from a regular mile?

A nautical mile is defined as exactly 1,852 meters (about 1.151 regular miles). It is based on the Earth's circumference and is used for navigation at sea and in aviation. A regular (statute) mile is 1,609.344 meters. The converter supports both units in the length category.

Related Tools

Time Unit ConversionConvert between 12-hour, 24-hour, and decimal time formatsTime Units CalculatorConvert between seconds, minutes, hours, days, weeks, and yearsDistance CalculatorCalculate the distance between cities worldwideRoman Numeral ConverterConvert numbers to and from Roman numerals

Data Sources and Accuracy

  • Convert library (npm: convert) - TypeScript-native unit conversion with zero dependencies
  • International System of Units (SI) - defines the meter, kilogram, second, and other base units
  • NIST Handbook 44 - specifications for US customary units and their SI equivalents
  • ISO 80000 - international standard for quantities and units
  • Binary prefixes (IEC 60027-2) - defines KiB, MiB, GiB for digital storage

All conversions use internationally defined conversion factors and are accurate to the full precision of the factor. US customary units are used by default for liquid measures (gallon, pint, cup). For imperial (UK) units, apply the appropriate conversion factor manually. Data storage conversions use binary conventions (1024-based) consistent with operating system reporting. For scientific or legal applications requiring certified accuracy, consult NIST or ISO documentation directly.