19 units across 4 measurement systems — metric, imperial, Chinese & nautical
Enter a value in any field — all 19 units recalculate
Type into any field — use the unit you know
All 19 units update instantly as you type
Click Copy next to any value
| Unit | Symbol | System | 1 Unit = (in meters) |
|---|---|---|---|
| Kilometre | km | Metric (SI) | 1,000 |
| Metre | m | Metric (SI base) | 1 |
| Decimetre | dm | Metric | 0.1 |
| Centimetre | cm | Metric | 0.01 |
| Millimetre | mm | Metric | 0.001 |
| Micrometre | µm | Metric | 0.000001 (10−6) |
| 里 (Li) | 里 | Chinese Traditional | 500 |
| 丈 (Zhang) | 丈 | Chinese Traditional | 3.333… (10/3) |
| 尺 (Chi) | 尺 | Chinese Traditional | 0.3333… (1/3) |
| 寸 (Cun) | 寸 | Chinese Traditional | 0.03333… (1/30) |
| 分 (Fen) | 分 | Chinese Traditional | 0.003333… (1/300) |
| 厘 (Li-milli) | 厘 | Chinese Traditional | 0.0003333… (1/3000) |
| Mile | mi | Imperial / US Customary | 1,609.344 |
| Furlong | fur | Imperial | 201.168 |
| Yard | yd | Imperial / US Customary | 0.9144 |
| Foot | ft | Imperial / US Customary | 0.3048 |
| Inch | in | Imperial / US Customary | 0.0254 |
| Nautical Mile | nmi | Nautical / Aviation | 1,852 |
| Fathom | ftm | Nautical | 1.8288 |
The Metric System (SI) is the global scientific and everyday standard, used by 195+ countries. Defined around the meter — originally 1/10,000,000 of the distance from the equator to the North Pole, now defined by the distance light travels in 1/299,792,458 of a second. Its decimal base-10 structure makes conversions trivial: move the decimal point. This is why scientists, engineers, and most of the world use metric.
Imperial and US Customary units persist in the United States, United Kingdom (partially), Liberia, and Myanmar. The foot, yard, and mile descend from Roman and Anglo-Saxon measures. A mile comes from mille passus (Latin for "a thousand paces"), standardized to 5,280 feet under Queen Elizabeth I. Despite metrication efforts, imperial units remain deeply embedded in American road signs, construction (lumber is sold in feet and inches), sports (football fields in yards), and everyday conversation.
Chinese traditional units are not museum pieces — they remain in active use across China, Taiwan, Hong Kong, and diaspora communities worldwide. The Li (里) is the standard long-distance unit in everyday Chinese speech: people say a town is "10 Li away," not "5 kilometers." The Chi (尺), roughly a foot, is the traditional unit for body measurements in Chinese medicine and tailoring. The Cun (寸), about the width of a thumb at the knuckle, is used in acupuncture to locate points on the body — the "cun" is literally defined as the width of the patient's thumb. The Zhang (丈) (10 Chi) appears in real estate and traditional architecture. Unlike imperial units, Chinese units use a consistent decimal structure: 1 Li = 150 Zhang, 1 Zhang = 10 Chi, 1 Chi = 10 Cun, 1 Cun = 10 Fen, 1 Fen = 10 Li-milli. The system is fully decimal — arguably more logical than the imperial system's 12 inches per foot and 5,280 feet per mile.
Historically, these units date back to the Shang Dynasty (~1600 BCE) and were standardized across the empire by Qin Shi Huang in 221 BCE. Their exact values have shifted over dynasties, but the modern PRC standardized them against the metric system: 1 Chi = 1/3 meter exactly, making 1 Li = 500 meters. This means Chinese units and metric units interoperate cleanly — a bridge no imperial system ever achieved.
All 19 units convert through meters (m) as the base unit. Input value → convert to meters using the unit's factor → convert to all other units. This eliminates accumulated rounding errors:
miles → m: miles × 1609.344 · feet → m: ft × 0.3048 · inches → m: in × 0.0254 · km → m: km × 1000
Li → m: Li × 500 · Chi → m: Chi ÷ 3 · Cun → m: Cun ÷ 30 · nmi → m: nmi × 1852 · fathom → m: ftm × 1.8288
| From | To | Multiply By | Example |
|---|---|---|---|
| Kilometres | Miles | × 0.621371 | 10 km = 6.21 mi |
| Miles | Kilometres | × 1.609344 | 5 mi = 8.05 km |
| Metres | Feet | × 3.28084 | 2 m = 6.56 ft |
| Feet | Metres | × 0.3048 | 10 ft = 3.048 m |
| Centimetres | Inches | × 0.393701 | 10 cm = 3.94 in |
| Inches | Centimetres | × 2.54 | 12 in = 30.48 cm |
| Li (里) | Kilometres | × 0.5 | 10 Li = 5 km |
| Li (里) | Miles | × 0.310686 | 10 Li = 3.11 mi |
| Chi (尺) | Feet | × 1.09361 | 3 Chi = 3.28 ft |
| Cun (寸) | Inches | × 1.31234 | 1 Cun = 1.31 in |
| Nautical Miles | Kilometres | × 1.852 | 100 nmi = 185.2 km |
| Nautical Miles | Statute Miles | × 1.15078 | 100 nmi = 115.1 mi |
Enter your value in the Metre (m) field. The Foot (ft) field shows the result instantly. 1 meter = 3.28084 feet. For quick mental math, multiply by 3.3. Example: 10 m = 32.81 ft.
Type your km value into the Kilometre field. The Mile field updates automatically. 1 km = 0.621371 miles. A 5K race is 3.11 miles; a 10K is 6.21 miles; a marathon (42.195 km) is exactly 26 miles 385 yards.
Chinese traditional units are actively used in China, Taiwan, and diaspora communities. Li (里) = 500 m (everyday distance: "the next town is 10 Li away"). Zhang (丈) = 3.333 m (real estate, architecture). Chi (尺) = 0.333 m (~13.1 in) (body measurements, tailoring). Cun (寸) = 3.33 cm (~1.31 in) (acupuncture, the width of a thumb knuckle). Fen (分) = 3.33 mm and Li-milli (厘) = 0.333 mm round out the system. All are decimal-based, making conversions within the Chinese system straightforward.
1 Li (里) = 0.5 km exactly = 0.310686 miles. To convert: Li × 0.5 = km, or Li ÷ 2 = km. For miles: Li × 0.310686. This converter handles all six Chinese traditional units — enter a value in any Chinese unit and see metric and imperial equivalents instantly.
A nautical mile (nmi) = 1,852 meters exactly, while a statute mile (mi) = 1,609.344 meters. The nautical mile is based on the Earth's circumference: 1 nmi = 1 minute of latitude (1/60 of a degree). This makes navigation math on charts dramatically simpler — distance directly relates to angular measurement. Ships and aircraft worldwide use nautical miles for navigation, knots for speed, and fathoms for depth. A fathom = 6 feet = 1.8288 meters, traditionally the span of a sailor's outstretched arms, still used for depth soundings on nautical charts.