Convert between any units of length, weight, volume, temperature, area, speed, time, and digital storage.
Whether you're cooking a recipe that uses grams when you only have measuring cups, planning a run in kilometers when you think in miles, or downloading a file and trying to gauge its size — our unit converter handles 8 categories of measurement with dozens of units each. Select a category, choose your units, and get an instant conversion.
| From | To | Multiply by |
|---|---|---|
| Miles | Kilometers | 1.60934 |
| Kilometers | Miles | 0.62137 |
| Feet | Meters | 0.3048 |
| Inches | Centimeters | 2.54 |
| Yards | Meters | 0.9144 |
| From | To | Multiply by |
|---|---|---|
| Pounds (lbs) | Kilograms | 0.453592 |
| Kilograms | Pounds | 2.20462 |
| Ounces | Grams | 28.3495 |
| Stone | Pounds | 14 |
Temperature conversions use special formulas (not simple multiplication):
The United States is one of only three countries in the world (alongside Myanmar and Liberia) that has not officially adopted the International System of Units (SI), commonly known as the metric system. The rest of the world — including Canada, Australia, the United Kingdom, and most of Europe — uses metric for everyday measurements.
This creates a regular need for conversions. Americans traveling abroad need to think in kilometers, kilograms, and Celsius. Scientists and engineers worldwide use metric. Medical dosing, global trade, and international recipes often require converting between the two systems.
The metric system is based on powers of 10, making math simple — 1 kilometer = 1,000 meters = 100,000 centimeters. Imperial units, by contrast, have irregular ratios: 1 mile = 1,760 yards = 5,280 feet = 63,360 inches. Our converter handles all of it automatically.
With the explosion of digital files, streaming, and cloud storage, understanding digital storage units has become practically essential. Here's how they relate:
Note: Storage manufacturers often use decimal prefixes (where 1 KB = 1,000 bytes), which is why a "1 TB" hard drive shows up as about 931 GB on your computer. Our calculator uses the binary definitions above, which is what operating systems report.