Unit Converter — Essential Conversions for Everyday Life
Common unit conversions everyone should know. Convert length, weight, temperature, speed, and data units instantly with our free tool.
I grew up with the metric system, then moved to the US for a few years. The number of times I've had to convert Celsius to Fahrenheit in my head while staring at an oven is embarrassing. Unit conversion is one of those things that nobody thinks about until they need it — and then they need it fast.
Why This Stuff Still Matters
Most of the world uses the metric system. The US clings to imperial units. The UK uses both, sometimes in the same sentence. If you cook from international recipes, work with overseas teams, or travel, you're converting units constantly.
The Conversions I Actually Use
Length
| From | To | Multiply by |
|---|---|---|
| Inches | Centimeters | 2.54 |
| Feet | Meters | 0.3048 |
| Miles | Kilometers | 1.60934 |
| Kilometers | Miles | 0.621371 |
Weight
| From | To | Multiply by |
|---|---|---|
| Pounds | Kilograms | 0.453592 |
| Kilograms | Pounds | 2.20462 |
| Ounces | Grams | 28.3495 |
Temperature
Temperature is the one you can't just multiply — you need a formula:
- Celsius to Fahrenheit: x 9/5 + 32
- Fahrenheit to Celsius: (- 32) x 5/9
- Celsius to Kelvin: + 273.15
Speed
| From | To | Multiply by |
|---|---|---|
| mph | km/h | 1.60934 |
| km/h | mph | 0.621371 |
| m/s | km/h | 3.6 |
Data Storage
This one catches people out because the ratio is 1024, not 1000:
| Unit | Equals |
|---|---|
| 1 KB | 1,024 bytes |
| 1 MB | 1,024 KB |
| 1 GB | 1,024 MB |
| 1 TB | 1,024 GB |
Why I Stopped Memorizing
I used to keep these factors in my head. Then I realized: my phone is always with me, and a unit converter is faster and more reliable than mental math. The one on this site handles length, weight, temperature, speed, and data storage — no ads, no signup.