Unit Converter
Convert between units of length, weight, temperature, volume, time, data, energy and more.
By Syed Mubashir Ali · Last updated
Common conversions
The conversions people look up most, rounded to three or four figures. Enter any value in the converter above for an exact answer.
| Conversion | Equals |
|---|---|
| 1 inch | 2.54 cm (exactly) |
| 1 foot | 30.48 cm (exactly) |
| 1 meter | 3.281 feet |
| 1 mile | 1.609 km |
| 1 km | 0.621 miles |
| 1 kg | 2.205 lb |
| 1 lb | 0.454 kg |
| 1 oz | 28.35 g |
| 1 stone | 6.35 kg (14 lb) |
| °C to °F | (°C × 9/5) + 32, so 20 °C = 68 °F |
| 1 US gallon | 3.785 L |
| 1 UK gallon | 4.546 L |
| 1 acre | 0.405 hectares |
| 100 km/h | 62.1 mph |
| 1 day | 24 hours |
| 1 GB | 1,024 MB |
| 1 kWh | 3,412 BTU |
| 1 bar | 14.5 psi |
| 180° | π radians (3.1416) |
| 1 cup of flour | about 125 g |
| 30 mpg (US) | 7.84 L/100 km |
How to Use Unit Converter
- 1Select a measurement category using the category tabs — fourteen of them, from Length and Weight to Time, Data storage, Energy, Cooking and Fuel consumption.
- 2Choose the 'from' unit in the left dropdown and the 'to' unit in the right dropdown.
- 3For Cooking, pick the ingredient first — cups convert to grams by density, so flour and honey give different answers.
- 4Enter the value you want to convert in the left input field.
- 5The converted result appears instantly in the right field, with the formula for one unit shown underneath.
- 6Click the ⇄ swap button to reverse the conversion, click any row in the reference table to set it as the target unit, or tap a recent conversion to run it again.
Frequently Asked Questions
How do I convert cm to inches?
Choose Length, set the 'from' unit to Centimeter (cm) and the 'to' unit to Inch (in), then type the number. 1 cm is 0.393701 inches, and 1 inch is exactly 2.54 cm, so 30 cm is 11.81 inches and 170 cm is 66.93 inches.
How do I convert kg to lbs?
Choose Weight / Mass, set Kilogram (kg) to Pound (lb), and type the weight. 1 kg is 2.20462 lb, so 70 kg is 154.32 lb. Going the other way, 1 lb is 0.453592 kg.
How do I convert Celsius to Fahrenheit?
Choose Temperature and set Celsius (°C) to Fahrenheit (°F). The formula is °F = (°C × 9/5) + 32, so 20 °C is 68 °F and 100 °C is 212 °F. Temperature uses offset formulas rather than a single multiplier, and the converter applies them for you, including Kelvin (K = °C + 273.15).
Which unit categories are supported?
Fourteen: Length (mm, cm, m, km, in, ft, yd, mi, nautical mile), Weight/Mass (mg, g, kg, metric ton, oz, lb, stone), Temperature (°C, °F, K), Volume (ml, L, m³, tsp, tbsp, fl oz, cup, US and UK pints, quart, US and UK gallons), Area (mm², cm², m², km², hectare, acre, ft², mi²), Speed (m/s, km/h, mph, knot, ft/s), Time (ms, s, min, h, day, week, month, year), Data storage (bit, B, KB, MB, GB, TB, PB), Energy (J, kJ, cal, kcal, Wh, kWh, BTU), Power (W, kW, MW, hp, BTU/h), Pressure (Pa, kPa, bar, psi, atm, mmHg, inHg), Angle (degrees, radians, gradians, turns, arcminutes, arcseconds), Cooking (cups, spoons and ml to grams by ingredient) and Fuel consumption (L/100 km, km/L, mpg US and UK).
How do I convert cups to grams?
Choose Cooking, pick the ingredient, then set the 'from' unit to Cup (US) and the 'to' unit to Gram (g). A cup is a volume, so the answer depends on what is in it: 1 cup of flour is about 125 g, 1 cup of sugar about 201 g and 1 cup of honey about 336 g. The converter uses typical densities, shown next to each ingredient — for baking, weighing is more accurate than converting.
What is L/100 km, and how does it relate to mpg?
L/100 km is how many litres a car uses per 100 kilometres — lower is better. Miles per gallon is the opposite: higher is better. Choose Fuel consumption to convert between them: 30 mpg (US) is 7.84 L/100 km, and 5 L/100 km is 47.04 mpg (US). UK gallons are bigger than US gallons, so the same car shows a higher mpg (UK) number — pick the right one.
Is this unit converter free? Do I need to sign up?
Yes, it's free, with no signup, no limits and nothing to install. Open the page and start converting.
Is my data private, and does it work offline?
Every conversion is worked out in your browser, so the numbers you type are never sent to a server. It works offline too: once you've opened the converter while online, it's saved on your device and opens and converts with no connection, even after you close the browser. You can also install Xplosole as an app.
How accurate are the conversions?
The converter uses precise conversion factors with up to 10 significant figures, and rounds the result to remove floating-point noise. Very large or very small results are shown in scientific notation (for example 1.5e+9) to keep them readable.
What do the Quick buttons and the copy button do?
The Quick buttons load four of the most searched conversions in one tap: 30 cm to inches, 5 kg to pounds, 100 °F to Celsius and 10 km to miles. The copy button next to the result copies the whole conversion as text, such as '10 km = 6.213711922 mi', ready to paste into a message or a document.
About Unit Converter
The Unit Converter provides instant conversion between units across fourteen measurement categories: length, weight, temperature, volume, area, speed, time, data storage, energy, power, pressure, angle, cooking and fuel consumption. With 98 units supported and a quick-reference table showing all conversions simultaneously, it covers the needs of students, engineers, cooks, travelers, and everyday users.
The quick-reference table at the bottom of the converter is a particularly powerful feature. When you enter a value, it shows what that value equals in every other unit in the category, all at once. This is especially useful when you're unsure which unit you need. You can scan the entire list and pick the most appropriate one.
Temperature conversion is handled with special care because temperature scales are offset-based rather than ratio-based. You can't simply multiply by a constant. You need to apply the correct formula. The converter handles Celsius, Fahrenheit, and Kelvin conversions automatically using the precise offset formulas, eliminating a common source of errors.
Volume conversion is particularly valuable for cooking and recipe scaling. Converting between metric (ml, L) and US customary (teaspoon, tablespoon, cup, pint, quart, gallon) units is a daily need for anyone cooking from international recipes, and UK pints and gallons are there too: a UK gallon is 4.546 litres, about 20% more than a US gallon.