Unit Conversion Calculator
Convert between units of length, weight, volume, temperature, area, and more
Common Conversion Formulas
All-in-One Unit Converter
This universal unit converter handles all common measurement types in one place. Whether you need to convert lengths for a DIY project, weights for shipping, volumes for cooking, or temperatures for travel, this tool provides instant, accurate conversions across metric, imperial, and specialized units.
The world uses two main measurement systems: metric (SI) used by most countries, and imperial/US customary units used primarily in the United States. Scientists, engineers, travelers, and anyone working internationally needs to move fluidly between these systems.
Our converter covers eight major categories—length, weight, volume, temperature, area, speed, time, and digital storage—with dozens of units in each category. Simply select your category, enter your value, choose your units, and get instant results.
Measurement Categories
Length/Distance
Meters, feet, inches, miles, kilometers, yards, centimeters, millimeters, nautical miles.
Weight/Mass
Kilograms, pounds, ounces, grams, tons, stones, milligrams, micrograms.
Volume
Liters, gallons, cups, fluid ounces, milliliters, tablespoons, teaspoons, pints, quarts.
Temperature
Celsius, Fahrenheit, Kelvin, Rankine. Essential for weather, cooking, and science.
Quick Reference: Common Conversions
| Conversion | Factor | Example | Category |
|---|---|---|---|
| Inches → Cm | × 2.54 | 12 in = 30.48 cm | Length |
| Pounds → Kg | × 0.4536 | 150 lb = 68 kg | Weight |
| Miles → Km | × 1.609 | 60 mi = 96.5 km | Length |
| Gallons → Liters | × 3.785 | 10 gal = 37.85 L | Volume |
| °F → °C | (°F-32)×5/9 | 98.6°F = 37°C | Temp |
| Ounces → Grams | × 28.35 | 8 oz = 227 g | Weight |
Conversion Tips by Use Case
Travel
Know km↔mi for driving, °C↔°F for weather, and kg↔lb for luggage limits. Most countries use metric.
Cooking
US recipes use cups/oz, international use grams/mL. 1 cup ≈ 240mL, 1 oz ≈ 28g.
Fitness
Convert weights (lb↔kg) and distances (mi↔km) for international workout programs.
DIY/Construction
Convert between inches/feet and centimeters/meters. 1 inch = 2.54 cm exactly.
Frequently Asked Questions
Why does the US use different units than other countries?
The US adopted the British Imperial system before the metric system became standard. While officially recognizing metric, the US never mandated conversion for everyday use. Cost, habit, and infrastructure keep imperial units in common use.
Which measurement system is more accurate?
Both are equally accurate—they're just different scales. Metric is arguably easier for calculations because it's base-10 (1 km = 1000 m), while imperial has arbitrary relationships (1 mile = 5280 feet).
How do I remember common conversions?
Use benchmarks: 1 inch ≈ 2.5 cm, 1 kg ≈ 2.2 lb, 1 mile ≈ 1.6 km, 1 liter ≈ 1 quart. For temperature: 0°C = freezing, 20°C = room temp, 37°C = body temp.
Are online converters accurate?
Reputable converters use exact conversion factors and are highly accurate. For critical applications (engineering, medicine), always verify with official conversion factors and consider significant figures.
Pro Tips
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