Free Unit Converter Online
Convert between length, weight, volume, and speed units.
Enter a value and click Convert to see results
Usage Examples
1 meter to all length units
1 m = 3.28 ft = 39.37 in = 0.001 km
1 mile in feet
5280 ft = 1 mi = 1609.344 m
1 kilogram to pounds and ounces
1 kg = 2.2046 lb = 35.274 oz
Average adult weight in pounds to kg
150 lb = 68.04 kg = 2400 oz
1 US gallon to liters
1 gal = 3.785 L = 4 qt = 16 cups
Highway speed: 100 km/h in mph
100 km/h = 62.14 mph = 27.78 m/s
How to Use Unit Converter
Select a Category
Choose Length, Weight, Volume, or Speed from the tabs.
Enter a Value
Type the numeric value you want to convert.
View All Conversions
See the value converted to all units in the selected category simultaneously.
Frequently Asked Questions
Basics
What units are supported?
Length: m, km, mi, ft, in, cm, mm. Weight: kg, g, lb, oz, ton. Volume: L, mL, gal, qt, cup, fl oz. Speed: m/s, km/h, mph, knots.
How accurate are the conversions?
Conversions use standard SI-defined factors and are accurate to at least 6 decimal places. For example, 1 mile = exactly 1609.344 meters.
Can I convert between categories?
No, you can only convert within the same category (e.g., length to length). Switch tabs to convert in different categories.
Common Conversions
How many feet in a meter?
1 meter = 3.28084 feet. This is a standard SI-to-imperial conversion used in engineering and construction.
How many kilograms in a pound?
1 pound = 0.453592 kg. Conversely, 1 kg = 2.20462 lb.
How do I convert km/h to mph?
Multiply km/h by 0.621371. For a quick estimate, divide by 1.6. For example, 100 km/h ≈ 62 mph.
How many liters in a gallon?
1 US gallon = 3.78541 liters. Note that UK (imperial) gallons are larger at 4.54609 liters, but this tool uses US gallons.