Why Unit Conversion Matters
The world uses two main unit systems — the metric system (used by most countries) and the imperial system (used primarily in the US). Understanding how to convert between them is essential for cooking, travel, science, and everyday life.
Temperature Conversion
Temperature is the most commonly needed conversion when traveling.
| Formula | Equation |
|---|
| Celsius → Fahrenheit | °F = (°C × 9/5) + 32 |
| Fahrenheit → Celsius | °C = (°F − 32) × 5/9 |
| Celsius → Kelvin | K = °C + 273.15 |
Key Temperature References
- Water freezes: 0°C / 32°F
- Room temperature: 20°C / 68°F
- Body temperature: 37°C / 98.6°F
- Water boils: 100°C / 212°F
Length Conversion
| From | To | Multiply by |
|---|
| Inches | Centimeters | × 2.54 |
| Centimeters | Inches | × 0.3937 |
| Feet | Meters | × 0.3048 |
| Meters | Feet | × 3.2808 |
| Miles | Kilometers | × 1.6093 |
| Kilometers | Miles | × 0.6214 |
| Yards | Meters | × 0.9144 |
Weight Conversion
| From | To | Multiply by |
|---|
| Pounds | Kilograms | × 0.4536 |
| Kilograms | Pounds | × 2.2046 |
| Ounces | Grams | × 28.3495 |
| Grams | Ounces | × 0.03527 |
| Stone | Kilograms | × 6.3503 |
| Tons (US) | Kilograms | × 907.185 |
Volume Conversion
| From | To | Multiply by |
|---|
| US Gallons | Liters | × 3.7854 |
| Liters | US Gallons | × 0.2642 |
| Fluid Ounces | Milliliters | × 29.5735 |
| Cups | Milliliters | × 236.588 |
| Tablespoons | Milliliters | × 14.787 |
Area Conversion
| From | To | Multiply by |
|---|
| Square feet | Square meters | × 0.0929 |
| Square meters | Square feet | × 10.7639 |
| Acres | Hectares | × 0.4047 |
| Square miles | Square km | × 2.58999 |
Speed Conversion
- 1 mph = 1.60934 km/h
- 1 km/h = 0.62137 mph
- 60 mph ≈ 97 km/h
- 100 km/h ≈ 62 mph
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