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Unit Converter guide

The Unit Converter translates values between Length, Weight, Temperature, and Volume. It uses precise standard conversion factors to ensure accuracy across both metric and imperial systems.

Worked examples

Convert Kilometers to Miles

  1. Select the "Length" tab.
  2. Enter 10 as the value.
  3. Choose Kilometers (km) as the From unit.
  4. Choose Miles (mi) as the To unit.
Result: 10 km = 6.2137 mi

1 kilometer is equal to approximately 0.621371 miles. 10 × 0.621371 = 6.21371.

Convert Celsius to Fahrenheit

  1. Select the "Temperature" tab.
  2. Enter 100 as the value.
  3. Choose Celsius (°C) as the From unit.
  4. Choose Fahrenheit (°F) as the To unit.
Result: 100 °C = 212 °F

The formula is °F = (°C × 9/5) + 32. (100 × 1.8) + 32 = 180 + 32 = 212.

Convert Pounds to Kilograms

  1. Select the "Weight" tab.
  2. Enter 150.
  3. Choose Pounds (lb) as the From unit.
  4. Choose Kilograms (kg) as the To unit.
Result: 150 lb = 68.0389 kg

1 pound is exactly 0.45359237 kilograms. 150 × 0.45359237 = 68.0388555.

Tips

  • •Unlike length or weight, temperature conversions use formulas with offsets, not just multiplication.
  • •The Volume tab uses US customary units (e.g., US gallons), which differ from UK imperial units.
  • •You can swap the From and To units instantly.

Frequently asked questions

What is the difference between the metric and imperial systems?
The metric system (used globally) is based on powers of 10 (meters, grams, liters). The imperial system (used mainly in the US) uses historical ratios (inches, pounds, gallons).
Why does temperature need a special formula?
Because temperature scales have different zero points (0°C is freezing, 32°F is freezing). You must multiply by the scale factor AND add an offset.
What is the difference between mass and weight?
Mass is the amount of matter (measured in kg). Weight is the force of gravity on that mass (measured in Newtons). In everyday use, "weight" usually means mass.
How many ounces are in a pound?
There are exactly 16 ounces in 1 pound.
How many feet are in a mile?
There are exactly 5,280 feet in one mile.
How many milliliters are in a liter?
There are 1,000 milliliters in 1 liter.
What is the difference between a US gallon and a UK gallon?
A US gallon is about 3.785 liters. A UK (imperial) gallon is about 4.546 liters. The tool uses US gallons.
Is 1 cm exactly 0.393701 inches?
Yes. 1 inch is defined as exactly 2.54 cm, so 1 cm is 1 / 2.54 = 0.393700787... inches.
Can I convert between volume and weight?
Not directly without density. A liter of water weighs 1 kg, but a liter of oil weighs less. This tool only converts within the same category.
How do I convert Celsius to Kelvin?
K = °C + 273.15.
What is absolute zero?
The lowest possible temperature, where particles have minimal motion. It is 0 Kelvin, -273.15 °C, or -459.67 °F.
How many grams are in a kilogram?
There are 1,000 grams in 1 kilogram.
What is a nautical mile?
A unit of distance used in aviation and sailing. It is equal to 1,852 meters. The tool does not currently convert nautical miles.
How do I convert fluid ounces to cups?
There are 8 US fluid ounces in 1 US cup.
Are the conversion factors exact?
Most imperial-to-metric factors (like inches to cm) are exact by definition. Some are rounded for display.
Can I convert area or volume?
This tool converts linear length and 3D capacity. For area (sq ft to sq m), you must square the conversion factor.
Why does 1 kg not equal exactly 2.2 lbs?
1 kg is exactly 2.2046226218 lbs. It is often rounded to 2.2 for simplicity, but the calculator uses full precision.
How precise are the results?
Results are rounded to 6 decimal places to provide high accuracy without visual clutter.
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