Unit Converter

Convert between 8 categories of units instantly. Real-time conversion as you type.

Formula: Select units to see the formula

Quick Reference

How to Use the Unit Converter

  1. Select a category — Choose from 8 categories: Length, Weight, Temperature, Volume, Area, Speed, Time, or Data. Each category has its own set of units.
  2. Choose your units — Select the source unit and target unit from the dropdown menus. Enter a number in the input field.
  3. Read the result — The converted value appears instantly as you type. The formula box below shows the exact conversion factor being used.

How Unit Conversion Works

Unit conversion uses multiplication by a conversion factor. Each unit is defined relative to a base unit for its category. For example, in the Length category, the base unit is the meter. 1 kilometer = 1000 meters, 1 foot = 0.3048 meters. To convert kilometers to feet, the converter multiplies by 1000 (km to meters) then divides by 0.3048 (meters to feet).

Temperature is the exception — it uses formulas rather than simple multiplication because the scales have different zero points. Celsius to Fahrenheit uses F = (C x 9/5) + 32, while Kelvin starts at absolute zero (-273.15 degrees Celsius).

Common Use Cases

Did You Know?

The metric system (SI) is used by every country in the world except the United States, Myanmar, and Liberia. Even in the US, science, medicine, and the military use metric. The conversion factor approach used by this converter is the same method taught in physics and engineering courses worldwide.

Most Common Conversions

ConversionExact ValueCategory
1 cm= 0.3937 inchesLength
1 inch= 2.54 cmLength
1 meter= 3.2808 feetLength
1 foot= 0.3048 metersLength
1 km= 0.6214 milesLength
1 mile= 1.6093 kmLength
1 kg= 2.2046 lbsWeight
1 pound= 453.592 gWeight
1 ounce= 28.3495 gWeight
1 liter= 0.2642 gallons (US)Volume
1 gallon (US)= 3.7854 litersVolume
1 cup (US)= 236.588 mlVolume
1 tablespoon= 14.787 mlVolume
1 sq foot= 0.0929 sq metersArea
1 acre= 4,046.86 sq metersArea
1 hectare= 2.4711 acresArea
1 byte= 8 bitsData
1 GB= 1,024 MBData
1 mph= 1.6093 km/hSpeed
1 knot= 1.852 km/hSpeed

Metric to Imperial Quick Reference

MetricImperialConversion
1 millimeter0.0394 inchesmm × 0.03937 = in
1 centimeter0.3937 inchescm × 0.3937 = in
1 meter3.2808 feetm × 3.2808 = ft
1 kilometer0.6214 mileskm × 0.6214 = mi
1 gram0.0353 ouncesg × 0.03527 = oz
1 kilogram2.2046 poundskg × 2.2046 = lb
1 liter0.2642 gallonsL × 0.2642 = gal
1 milliliter0.0338 fluid ozml × 0.0338 = fl oz
1 sq meter10.7639 sq feetm² × 10.7639 = ft²
1 sq kilometer0.3861 sq mileskm² × 0.3861 = mi²

Temperature Comparison

DescriptionCelsius (°C)Fahrenheit (°F)Kelvin (K)
Absolute Zero−273.15−459.670
Water Freezes032273.15
Room Temperature20–2268–72293–295
Human Body3798.6310.15
Water Boils100212373.15
Oven (Baking)180–230350–450453–503
Surface of the Sun5,5059,9415,778

Frequently Asked Questions

How do I convert units online?

Select a category (length, weight, temperature, etc.), choose your source and target units from the dropdowns, then enter a number. The conversion happens instantly as you type. No button click needed.

What unit categories are supported?

This converter supports 8 categories: Length, Weight, Temperature, Volume, Area, Speed, Time, and Data. Each category includes multiple units like meters, feet, kilograms, pounds, Celsius, Fahrenheit, and more.

How accurate are the conversions?

All conversions use standard, internationally recognized conversion factors. Results are displayed with up to 10 significant digits for maximum accuracy. For scientific or engineering work, the precision is more than sufficient.

Can I convert between metric and imperial units?

Yes. The converter supports both metric (meters, kilograms, liters) and imperial (feet, pounds, gallons) systems. Simply select the metric unit in one field and the imperial unit in the other.

What is the formula for temperature conversion?

The tool shows the exact formula used for each conversion. For example, Celsius to Fahrenheit: F = (C x 9/5) + 32. Celsius to Kelvin: K = C + 273.15. The formula box updates automatically when you change units.

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