Tool Stack

Unit Converters

Convert between any units instantly — length, weight, temperature, data, pressure and more.

Length Converter

Convert meters, kilometers, miles, feet, inches, centimeters, yards, nautical miles and more.

Weight & Mass Converter

Convert kilograms, grams, pounds, ounces, metric tons, stone, milligrams and more.

Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin and Rankine.

Volume & Capacity Converter

Convert liters, milliliters, gallons, cups, fluid ounces, tablespoons, pints, quarts and more.

Area Converter

Convert square meters, square feet, acres, hectares, square kilometers and more.

Speed Converter

Convert km/h, mph, m/s, knots, and feet per second.

Time Converter

Convert seconds, minutes, hours, days, weeks, months, and years.

Data Storage Converter

Convert bytes, kilobytes, megabytes, gigabytes, terabytes, and bits.

Pressure Converter

Convert Pascal, kPa, MPa, bar, psi, atm, and mmHg.

Energy Converter

Convert joules, kilojoules, calories, kilocalories, watt-hours, kWh, BTU and more.

Angle Converter

Convert degrees, radians, gradians, arcminutes, and arcseconds.

Fuel Efficiency Converter

Convert between mpg (US), mpg (UK), km/L and L/100km.

About Online Unit Converters

Unit conversion is one of the most frequently needed — and most frequently botched — everyday calculations. A misread recipe doubles the salt because someone confused tablespoons with teaspoons. A project deadline gets missed because days were counted but time zones were not. A structural calculation goes wrong because an engineer accidentally mixed metric and imperial lengths. Our unit converter collection tackles twelve broad measurement categories, giving you fast, accurate conversions between all common units without requiring you to remember conversion factors or hunt through reference tables.

The importance of unit conversion stretches across virtually every domain of human activity. In science and engineering, working consistently in the correct units is not just a convenience — it is a safety requirement. In cooking and baking, precise volume and weight conversions determine whether a dish succeeds or fails. In travel and logistics, knowing whether a speed limit is in km/h or mph, or what a local petrol price per litre translates to in mpg, saves both time and money. In software development, understanding data storage units — from bits to terabytes — is essential when estimating storage costs or bandwidth usage. Our converters bring clarity to all of these situations in a single, always-accessible page.

Available Converters

  • Length — meters, kilometers, miles, feet, inches, centimeters, yards, nautical miles, and light years.
  • Weight / Mass — kilograms, grams, pounds, ounces, metric tons, milligrams, stone, and troy ounces.
  • Temperature — Celsius, Fahrenheit, Kelvin, and Rankine, using the correct non-linear formulas.
  • Volume / Capacity — liters, milliliters, gallons (US and UK), cups, fluid ounces, tablespoons, teaspoons, pints, and quarts.
  • Area — square meters, square feet, acres, hectares, square kilometers, square miles, and more.
  • Speed — km/h, mph, m/s, knots, and feet per second.
  • Time — milliseconds, seconds, minutes, hours, days, weeks, months, and years.
  • Data Storage — bits, kilobits, megabits, bytes, kilobytes, megabytes, gigabytes, and terabytes.
  • Pressure — Pascal, kilopascal, megapascal, bar, PSI, atmosphere, and mmHg.
  • Energy — joules, kilojoules, calories, kilocalories, watt-hours, kilowatt-hours, BTU, and electronvolts.
  • Angle — degrees, radians, gradians, arcminutes, and arcseconds.
  • Fuel Economy — mpg (US), mpg (UK), km/L, and L/100km.

Who Uses These Tools?

Engineers and scientists routinely convert between SI and imperial units when working with international suppliers, standards documents, or colleagues in different countries. Students use length and area converters for geography and physics assignments, and temperature converters for chemistry lab reports. Travellers check speed limit equivalents before renting a car abroad and use fuel economy converters to evaluate the cost of driving. Home cooks and professional chefs convert between volume and weight measurements when adapting recipes that use unfamiliar units. Programmers and system administrators rely on data storage converters when specifying disk sizes, calculating bandwidth, or debugging network throughput. Fitness enthusiasts convert between kilometers and miles when training on a foreign treadmill or following a running plan from another country.

Tips for Accurate Conversions

  • Always double-check critical conversions — for engineering or medical use, verify results against a second source before acting on them.
  • Understand the base unit for each category: the meter for length, the kilogram for mass, the second for time. All other units are multiples or fractions of these.
  • Temperature is special — unlike most units, Celsius-to-Fahrenheit conversion is not a simple multiplication. Our converter handles the correct formula (°F = °C × 9/5 + 32) automatically.
  • For cooking, note that volume and weight are not interchangeable without knowing ingredient density. One cup of flour weighs far less than one cup of water.

Frequently Asked Questions

  • The metric system (SI) is the international standard used by the scientific community, most governments, and almost every country in the world except the United States, Liberia, and Myanmar for everyday measurement. It is generally considered easier to work with because all units are based on powers of ten — converting kilometers to meters is simply a matter of multiplying by 1,000. Imperial units such as miles, pounds, and gallons remain common in the US and UK in everyday contexts. Our converters support both, so you can work in whichever system you prefer and convert whenever cross-system communication is needed.

  • The formula is: °F = (°C × 9/5) + 32. So 0°C (water's freezing point) equals 32°F, and 100°C (boiling point at sea level) equals 212°F. A quick mental shorthand: double the Celsius temperature and add 30 — this gives a rough estimate that is close enough for many everyday purposes. For precise conversions, use our temperature converter which applies the exact formula automatically.

  • A kilobyte (KB) is officially defined as 1,000 bytes in the SI standard. A kibibyte (KiB) is defined as 1,024 bytes (2¹⁰) under the IEC binary prefix standard. Historically, the computer industry used "kilobyte" to mean 1,024 bytes, which caused persistent confusion when hard drive manufacturers began using the SI definition (1,000 bytes), making drives appear smaller than advertised. Our data storage converter uses the SI (decimal) definitions by default — KB = 1,000, MB = 1,000,000, GB = 1,000,000,000 — which aligns with how storage capacity is marketed.

  • For most unit pairs, yes — the conversion factors used are the internationally agreed exact values (e.g., 1 inch = exactly 2.54 cm; 1 mile = exactly 1.609344 km). Some conversions involving derived or approximate definitions — such as the calorie, the BTU, or the average month — are based on the most widely accepted conventional values. All arithmetic is performed in JavaScript's 64-bit floating-point, which provides 15–17 significant decimal digits of precision, more than enough for any practical conversion task.