| chain | 1 ch | 2 ch | 3 ch | 4 ch | 5 ch | 6 ch | 7 ch | 8 ch | 9 ch | 10 ch | 11 ch | 12 ch | 13 ch | 14 ch | 15 ch | 16 ch | 17 ch | 18 ch | 19 ch | 20 ch | 21 ch | 22 ch | 23 ch | 24 ch | 25 ch | 26 ch | 27 ch | 28 ch | 29 ch | 30 ch | 31 ch | 32 ch | 33 ch | 34 ch | 35 ch | 36 ch | 37 ch | 38 ch | 39 ch | 40 ch | 41 ch | 42 ch | 43 ch | 44 ch | 45 ch | 46 ch | 47 ch | 48 ch | 49 ch | 50 ch | 51 ch | 52 ch | 53 ch | 54 ch | 55 ch | 56 ch | 57 ch | 58 ch | 59 ch | 60 ch | 61 ch | 62 ch | 63 ch | 64 ch | 65 ch | 66 ch | 67 ch | 68 ch | 69 ch | 70 ch | 71 ch | 72 ch | 73 ch | 74 ch | 75 ch | 76 ch | 77 ch | 78 ch | 79 ch | 80 ch | 81 ch | 82 ch | 83 ch | 84 ch | 85 ch | 86 ch | 87 ch | 88 ch | 89 ch | 90 ch | 91 ch | 92 ch | 93 ch | 94 ch | 95 ch | 96 ch | 97 ch | 98 ch | 99 ch | 100 ch |
| metric inch | 50,292.1 in (metric) | 100,584.2 in (metric) | 150,876.3 in (metric) | 201,168.4 in (metric) | 251,460.5 in (metric) | 301,752.6 in (metric) | 352,044.7 in (metric) | 402,336.8 in (metric) | 452,628.9 in (metric) | 502 921 in (metric) | 553,213.1 in (metric) | 603,505.2 in (metric) | 653,797.3 in (metric) | 704,089.4 in (metric) | 754,381.5 in (metric) | 804,673.6 in (metric) | 854,965.7 in (metric) | 905,257.8 in (metric) | 955,549.9 in (metric) | 1 005 842 in (metric) | 1,056,134.1 in (metric) | 1,106,426.2 in (metric) | 1,156,718.3 in (metric) | 1,207,010.4 in (metric) | 1,257,302.5 in (metric) | 1,307,594.6 in (metric) | 1,357,886.7 in (metric) | 1,408,178.8 in (metric) | 1,458,470.9 in (metric) | 1 508 763 in (metric) | 1,559,055.1 in (metric) | 1,609,347.2 in (metric) | 1,659,639.3 in (metric) | 1,709,931.4 in (metric) | 1,760,223.5 in (metric) | 1,810,515.6 in (metric) | 1,860,807.7 in (metric) | 1,911,099.8 in (metric) | 1,961,391.9 in (metric) | 2 011 684 in (metric) | 2,061,976.1 in (metric) | 2,112,268.2 in (metric) | 2,162,560.3 in (metric) | 2,212,852.4 in (metric) | 2,263,144.5 in (metric) | 2,313,436.6 in (metric) | 2,363,728.7 in (metric) | 2,414,020.8 in (metric) | 2,464,312.9 in (metric) | 2 514 605 in (metric) | 2,564,897.1 in (metric) | 2,615,189.2 in (metric) | 2,665,481.3 in (metric) | 2,715,773.4 in (metric) | 2,766,065.5 in (metric) | 2,816,357.6 in (metric) | 2,866,649.7 in (metric) | 2,916,941.8 in (metric) | 2,967,233.9 in (metric) | 3 017 526 in (metric) | 3,067,818.1 in (metric) | 3,118,110.2 in (metric) | 3,168,402.3 in (metric) | 3,218,694.4 in (metric) | 3,268,986.5 in (metric) | 3,319,278.6 in (metric) | 3,369,570.7 in (metric) | 3,419,862.8 in (metric) | 3,470,154.9 in (metric) | 3 520 447 in (metric) | 3,570,739.1 in (metric) | 3,621,031.2 in (metric) | 3,671,323.3 in (metric) | 3,721,615.4 in (metric) | 3,771,907.5 in (metric) | 3,822,199.6 in (metric) | 3,872,491.7 in (metric) | 3,922,783.8 in (metric) | 3,973,075.9 in (metric) | 4 023 368 in (metric) | 4,073,660.1 in (metric) | 4,123,952.2 in (metric) | 4,174,244.3 in (metric) | 4,224,536.4 in (metric) | 4,274,828.5 in (metric) | 4,325,120.6 in (metric) | 4,375,412.7 in (metric) | 4,425,704.8 in (metric) | 4,475,996.9 in (metric) | 4 526 289 in (metric) | 4,576,581.1 in (metric) | 4,626,873.2 in (metric) | 4,677,165.3 in (metric) | 4,727,457.4 in (metric) | 4,777,749.5 in (metric) | 4,828,041.6 in (metric) | 4,878,333.7 in (metric) | 4,928,625.8 in (metric) | 4,978,917.9 in (metric) | 5 029 210 in (metric) |
A chain is a unit of length. It measures 66 feet, or 22 yards, or 100 links, or 4 rods (20.1168 m). There are 10 chains in a furlong, and 80 chains in one statute mile. An acre is the area of 10 square chains (that is, an area of one chain by one furlong). The chain has been used for several centuries in Britain and in some other countries influenced by British practice.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| chain | ch | ≡ 66 ft (US) ≡ 4 rods | ≈ 20.11684 m | Imperial/US |
| chains | metric inches | chains | metric inches |
|---|---|---|---|
| 1 | ≈ 50292.1 | 4 | ≈ 201168.4 |
| 1.5 | ≈ 75438.15 | 4.5 | ≈ 226314.45 |
| 2 | ≈ 100584.2 | 5 | ≈ 251460.5 |
| 2.5 | ≈ 125730.25 | 5.5 | ≈ 276606.55 |
| 3 | ≈ 150876.3 | 6 | ≈ 301752.6 |
A metric inch is a nickname for a preferred 1⁄4 subdivision of an ISO 2848 basic module, or 1⁄12 of a metric foot measuring 25 millimetres (0.984 in). A metric inch is 0.4 millimetres (0.016 in) shorter than an inch.
The term was similarly used to refer to the historical Soviet Bloc practice of spacing integrated circuit pins at 1⁄10 of a 25 mm "metric inch" length, instead of the western practice of 1⁄10 of an imperial inch.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| metric inch | in (metric) | = 0.016 in | = 0.0004 m | Metric system SI |
| metric inches | chains | metric inches | chains |
|---|---|---|---|
| 1 | ≈ 1.9883838614812E-5 | 4 | ≈ 7.9535354459249E-5 |
| 1.5 | ≈ 2.9825757922218E-5 | 4.5 | ≈ 8.9477273766655E-5 |
| 2 | ≈ 3.9767677229625E-5 | 5 | ≈ 9.9419193074061E-5 |
| 2.5 | ≈ 4.9709596537031E-5 | 5.5 | ≈ 0.00010936111238147 |
| 3 | ≈ 5.9651515844437E-5 | 6 | ≈ 0.00011930303168887 |
| chains | metric inches |
|---|---|
| 1 | ≈ 50,292.1 |
| 1.9883838614812 × 10-5 | ≈ 1 |
| Symbol | Definition |
|---|---|
| ≡ | exactly equal |
| ≈ | approximately equal to |
| = | equal to |
| digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |