Length Converter — Meters, Feet, Inches, Kilometers, Miles
Length is one of the most commonly converted measurements, particularly between the metric system used by most of the world and the imperial system used in the United States.
Common length conversions:
| From | To | Multiply By |
|---|---|---|
| Inches | Centimeters | 2.54 |
| Feet | Meters | 0.3048 |
| Yards | Meters | 0.9144 |
| Miles | Kilometers | 1.60934 |
| Kilometers | Miles | 0.62137 |
| Meters | Feet | 3.28084 |
| Centimeters | Inches | 0.39371 |
Quick reference:
- 1 inch = 2.54 centimeters
- 1 foot = 30.48 centimeters
- 1 mile = 1.609 kilometers
- 1 meter = 3.281 feet
- 5 feet 9 inches = 175.26 centimeters
Length conversions are essential for international travel, construction, engineering, and everyday tasks like understanding clothing sizes or reading foreign recipes.
Weight Converter — Kilograms, Pounds, Ounces, Grams
Weight conversion is one of the most searched unit conversions globally, driven by international shipping, cooking, fitness, and medical applications.
Common weight conversions:
| From | To | Multiply By |
|---|---|---|
| Pounds | Kilograms | 0.45359 |
| Kilograms | Pounds | 2.20462 |
| Ounces | Grams | 28.3495 |
| Grams | Ounces | 0.03527 |
| Stones | Kilograms | 6.35029 |
| Kilograms | Stones | 0.15747 |
| Tons (US) | Kilograms | 907.185 |
Quick reference:
- 1 pound = 0.453 kilograms
- 1 kilogram = 2.205 pounds
- 1 ounce = 28.35 grams
- 150 pounds = 68.04 kilograms
- 100 kilograms = 220.46 pounds
Weight conversions are particularly useful for international travelers checking baggage limits, athletes tracking body weight, and home cooks following recipes from other countries.
Temperature Converter — Celsius, Fahrenheit, Kelvin
Temperature conversion is one of the most practical everyday conversions, used in cooking, weather forecasting, science, and medicine.
Conversion formulas:
| Conversion | Formula |
|---|---|
| Celsius to Fahrenheit | (°C × 9/5) + 32 |
| Fahrenheit to Celsius | (°F − 32) × 5/9 |
| Celsius to Kelvin | °C + 273.15 |
| Kelvin to Celsius | K − 273.15 |
| Fahrenheit to Kelvin | (°F − 32) × 5/9 + 273.15 |
Common temperature reference points:
| Description | Celsius | Fahrenheit |
|---|---|---|
| Water freezes | 0°C | 32°F |
| Room temperature | 20–22°C | 68–72°F |
| Normal body temperature | 37°C | 98.6°F |
| Water boils | 100°C | 212°F |
| Oven baking temperature | 175°C | 350°F |
Celsius is used by virtually every country in the world. Fahrenheit is used primarily in the United States. Kelvin is the standard unit in scientific and engineering applications.
Volume Converter — Liters, Gallons, Fluid Ounces, Cups
Volume conversions are essential for cooking, automotive applications, fuel measurement, and international product labeling.
Common volume conversions:
| From | To | Multiply By |
|---|---|---|
| Liters | US Gallons | 0.26417 |
| US Gallons | Liters | 3.78541 |
| Fluid Ounces | Milliliters | 29.5735 |
| Milliliters | Fluid Ounces | 0.03381 |
| Cups | Milliliters | 236.588 |
| Tablespoons | Milliliters | 14.7868 |
| Teaspoons | Milliliters | 4.92892 |
Quick reference:
- 1 liter = 33.814 fluid ounces
- 1 US gallon = 3.785 liters
- 1 cup = 236.6 milliliters
- 1 tablespoon = 14.79 milliliters
- 1 teaspoon = 4.93 milliliters
Note that the US gallon (3.785 liters) and the UK imperial gallon (4.546 liters) are different measurements. Always confirm which gallon is being referenced in international contexts.
Speed and Area Converter
Speed conversions:
| From | To | Multiply By |
|---|---|---|
| Miles per hour | Kilometers per hour | 1.60934 |
| Kilometers per hour | Miles per hour | 0.62137 |
| Meters per second | Kilometers per hour | 3.6 |
| Knots | Miles per hour | 1.15078 |
| Knots | Kilometers per hour | 1.852 |
Quick speed reference:
- 60 mph = 96.56 kph
- 100 kph = 62.14 mph
- Speed of sound = 343 m/s = 767 mph = 1,235 kph
Area conversions:
| From | To | Multiply By |
|---|---|---|
| Square feet | Square meters | 0.09290 |
| Square meters | Square feet | 10.7639 |
| Acres | Square meters | 4046.86 |
| Acres | Hectares | 0.40469 |
| Hectares | Acres | 2.47105 |
| Square miles | Square kilometers | 2.58999 |
Quick area reference:
- 1 acre = 43,560 square feet
- 1 hectare = 10,000 square meters = 2.471 acres
- 1 square mile = 640 acres = 2.59 square kilometers
Frequently Asked Questions
How many centimeters are in an inch?
There are exactly 2.54 centimeters in one inch. This is a defined conversion — it is not an approximation. To convert inches to centimeters, multiply the number of inches by 2.54. To convert centimeters to inches, divide by 2.54 or multiply by 0.3937.
How do I convert Celsius to Fahrenheit?
Multiply the Celsius temperature by 9/5 (or 1.8) and then add 32. For example, 25°C equals (25 × 1.8) + 32 = 77°F. To go the other direction, subtract 32 from the Fahrenheit temperature and multiply by 5/9. For example, 98.6°F equals (98.6 − 32) × 5/9 = 37°C.
How many pounds are in a kilogram?
One kilogram equals approximately 2.20462 pounds. To convert kilograms to pounds, multiply by 2.205. To convert pounds to kilograms, multiply by 0.4536. For example, 70 kilograms equals approximately 154.3 pounds, and 150 pounds equals approximately 68.04 kilograms.
How many feet are in a meter?
One meter equals approximately 3.28084 feet. To convert meters to feet, multiply by 3.281. To convert feet to meters, multiply by 0.3048. For example, 10 meters equals 32.81 feet, and 6 feet equals approximately 1.83 meters.
How many liters are in a gallon?
One US gallon equals approximately 3.785 liters. One UK imperial gallon equals approximately 4.546 liters. To convert US gallons to liters, multiply by 3.785. To convert liters to US gallons, multiply by 0.264. The difference between US and UK gallons is significant — always confirm which unit is being used.
How many miles per hour is 100 kilometers per hour?
100 kilometers per hour equals approximately 62.14 miles per hour. To convert kph to mph, multiply by 0.6214. To convert mph to kph, multiply by 1.6093. This conversion is particularly useful for international driving — a 100 kph speed limit is roughly equivalent to a 62 mph limit.
How do I convert square feet to square meters?
Multiply the number of square feet by 0.0929 to get square meters. For example, a 1,000 square foot apartment equals approximately 92.9 square meters. To convert square meters to square feet, multiply by 10.764.
How many ounces are in a pound?
There are exactly 16 ounces in one pound. This applies to avoirdupois ounces and pounds, which are used for most everyday measurements in the United States. Note that troy ounces — used for precious metals — are different: one troy pound contains 12 troy ounces.
Last updated: 2026 | Conversions based on NIST standards for weights and measures.