Last updated: May 2026
Convert any length or distance unit instantly — metric (mm, cm, m, km) to imperial (in, ft, yd, mi) and back.
Convert between metric (mm, cm, m, km) and imperial (in, ft, yd, mi)
Common Length References
| Metric | Imperial | Context |
|---|---|---|
| 1 cm | 0.394 in | Width of a fingernail |
| 30.48 cm | 1 ft | Standard foot |
| 1 m | 3.281 ft | Slightly longer than a yard |
| 1 km | 0.621 mi | About 12 city blocks |
| 5 km | 3.107 mi | 5K race distance |
| 42.195 km | 26.219 mi | Marathon |
Other Unit Converters
The world uses two major length systems that don't play nicely together: the metric system (millimeters, centimeters, meters, kilometers) and the imperial system (inches, feet, yards, miles). Most of the world uses metric; the US uses imperial for everyday life and metric for science. If you're buying furniture from a European store or calculating a road trip distance in unfamiliar units, this converter does the math instantly.
All metric conversions are powers of 10 — clean and predictable. Imperial conversions are the opposite: 12 inches per foot, 3 feet per yard, 1,760 yards per mile. There's no logical pattern. You just have to know them, or use a tool like this.
The most useful conversions for quick mental estimates:
| From | To | Multiply By | Quick Estimate |
|---|---|---|---|
| Inches | Centimeters | 2.54 | × 2.5, add ~2% |
| Centimeters | Inches | 0.3937 | ÷ 2.54 |
| Feet | Meters | 0.3048 | ≈ multiply by 0.3 |
| Meters | Feet | 3.2808 | ≈ multiply by 3.28 |
| Miles | Kilometers | 1.60934 | × 1.6 |
| Kilometers | Miles | 0.62137 | × 0.6 |
| Yards | Meters | 0.9144 | ≈ same as meters (within 9%) |
How many centimeters is 5 feet 11 inches?
Convert everything to inches first: 5 feet = 60 inches, plus 11 = 71 inches total. Then 71 × 2.54 = 180.34 cm. So 5'11" is approximately 180 cm.
What's the difference between a meter and a yard?
A meter is 3.281 feet; a yard is exactly 3 feet. A meter is about 9.36% longer than a yard. For rough estimates they're close enough that people sometimes confuse them — but the difference matters in construction, sports distances, and fabric measurement.
Is a mile longer than a kilometer?
Yes. One mile equals 1.60934 kilometers — so a mile is about 61% longer than a kilometer. A 5-mile drive is roughly 8 km; a 10 km run is just over 6 miles.
How do I convert height from feet and inches to centimeters?
Multiply total inches by 2.54. First convert everything to inches: (feet × 12) + remaining inches. Then multiply by 2.54. For 6'2": 6 × 12 = 72, plus 2 = 74 inches. 74 × 2.54 = 187.96 cm.
Why does the US still use inches and feet?
Mostly historical inertia. The US, Myanmar, and Liberia are the only countries that haven't officially adopted the metric system for everyday use. Multiple US metric conversion attempts have failed — most notably in the 1970s. Industry, science, and medicine in the US use metric; everyday life still runs on imperial.