Ever been confused by a 5.2 lb shipping weight on an overseas shopping site? Or wondered how many square feet a 33-pyeong Korean apartment is? Unit conversion is more common in daily life than you might think.
This guide covers the most frequently used conversion formulas for length, weight, temperature, area, data size, speed, pressure, and energy with practical examples.
📑 Table of Contents
1. Length Conversion
Length conversions are needed for monitor sizes (inches), travel (miles), and construction (feet).
| Conversion | Formula | Example |
|---|---|---|
| cm → inch | ÷ 2.54 | 170cm = 66.93in |
| inch → cm | × 2.54 | 27in = 68.58cm |
| ft → cm | × 30.48 | 5.9ft = 179.83cm |
| km → mile | × 0.6214 | 10km = 6.21mi |
Quick tip: To convert cm to feet/inches, divide by 2.54 to get total inches, then divide by 12 for feet. Example: 175cm ÷ 2.54 = 68.9in = 5'9".
📏 Length Converter Convert cm, inch, ft, m, km, and more →2. Weight Conversion
Weight conversions come up frequently in overseas shopping (lb), cooking (oz), and luggage limits (kg).
| Conversion | Formula | Example |
|---|---|---|
| kg → lb | × 2.2046 | 70kg = 154.32lb |
| lb → kg | × 0.4536 | 5.2lb = 2.36kg |
| oz → g | × 28.3495 | 8oz = 226.80g |
Quick tip: To estimate lb → kg, halve the lb value and subtract 10%. Example: 7.5lb ÷ 2 = 3.75, minus 10% ≈ 3.4kg (actual: 3.40kg).
⚖️ Weight Converter Convert kg, lb, oz, g, and more →3. Temperature Conversion
Korea uses Celsius while the US uses Fahrenheit. Key formulas:
| Conversion | Formula | Example |
|---|---|---|
| °C → °F | (°C × 9/5) + 32 | 36.5°C = 97.7°F |
| °F → °C | (°F − 32) × 5/9 | 350°F = 176.7°C |
| °C → K | °C + 273.15 | 0°C = 273.15K |
Common reference points: Water freezes at 0°C (32°F), body temperature is 36.5°C (97.7°F), and water boils at 100°C (212°F). For oven baking, 350°F ≈ 177°C.
🌡️ Temperature Converter Convert between Celsius, Fahrenheit, and Kelvin →