Unit of Measure Conversions
Length Conversions
Additional Units and Information
| Name | Symbol | Value | Description/Notes |
|---|---|---|---|
| ångström | Å | 1 x 10-10 metre | Equivalent to 100 picometres |
| chain | ch | 22 yards; 1/10 furlong |
Distance between wickets in a standard cricket pitch |
| fermi | fm | 1 x 10-15 metre | Equivalent to 1 femtometre |
| hand | 4 inches | Used to express a horse's height | |
| league | Land: 3 miles; Sea: 3 nautical miles |
Generally accepted values | |
| line | l | 1/12 inch | |
| link | 8 inches | ||
| marathon | 26 miles and 385 yards | 46,145 yards; 42,195 metres |
|
| micron | µm |
1 x 10-6 metre;
10,000 ångströms |
Equivalent to 1 micrometre |
| mil | 1/1000 inch | UK & US: "thou" | |
| mil | 10,000 metres | Norway & Sweden: "myriametre" | |
| nautical mile |
nm | 6,080 feet | UK nautical mile |
| pole | pl | 5½ yards; ¼ chain |
Also called "perch" & "rod" |
| X-unit | XU | 1 x 10-13 metre; 100 fm |
Used with X-ray wavelengths |
Useful Approximations
| Approximation | % Accuracy |
|---|---|
| The span of a man's outstretched hand (measured from thumb to second finger tip) ≈ 9 inches | |
| 1 link ≈ 1/100 chain | 99.0 |
| 1 mile ≈ 1.6 kilometres | 99.4 |
| 1 international nautical mile ≈ 1 UK nautical mile | 99.9 |