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 |
rod | 4.0000080 rd | 8.0000159 rd | 12.0000239 rd | 16.0000318 rd | 20.0000398 rd | 24.0000477 rd | 28.0000557 rd | 32.0000636 rd | 36.0000716 rd | 40.0000795 rd | 44.0000875 rd | 48.0000954 rd | 52.0001034 rd | 56.0001113 rd | 60.0001193 rd | 64.0001273 rd | 68.0001352 rd | 72.0001432 rd | 76.0001511 rd | 80.0001591 rd | 84.0001670 rd | 88.0001750 rd | 92.0001829 rd | 96.0001909 rd | 100.0001988 rd | 104.0002068 rd | 108.0002147 rd | 112.0002227 rd | 116.0002307 rd | 120.0002386 rd | 124.0002466 rd | 128.0002545 rd | 132.0002625 rd | 136.0002704 rd | 140.0002784 rd | 144.0002863 rd | 148.0002943 rd | 152.0003022 rd | 156.0003102 rd | 160.0003181 rd | 164.0003261 rd | 168.0003340 rd | 172.0003420 rd | 176.0003500 rd | 180.0003579 rd | 184.0003659 rd | 188.0003738 rd | 192.0003818 rd | 196.0003897 rd | 200.0003977 rd | 204.0004056 rd | 208.0004136 rd | 212.0004215 rd | 216.0004295 rd | 220.0004374 rd | 224.0004454 rd | 228.0004534 rd | 232.0004613 rd | 236.0004693 rd | 240.0004772 rd | 244.0004852 rd | 248.0004931 rd | 252.0005011 rd | 256.0005090 rd | 260.0005170 rd | 264.0005249 rd | 268.0005329 rd | 272.0005408 rd | 276.0005488 rd | 280.0005567 rd | 284.0005647 rd | 288.0005727 rd | 292.0005806 rd | 296.0005886 rd | 300.0005965 rd | 304.0006045 rd | 308.0006124 rd | 312.0006204 rd | 316.0006283 rd | 320.0006363 rd | 324.0006442 rd | 328.0006522 rd | 332.0006601 rd | 336.0006681 rd | 340.0006761 rd | 344.0006840 rd | 348.0006920 rd | 352.0006999 rd | 356.0007079 rd | 360.0007158 rd | 364.0007238 rd | 368.0007317 rd | 372.0007397 rd | 376.0007476 rd | 380.0007556 rd | 384.0007635 rd | 388.0007715 rd | 392.0007794 rd | 396.0007874 rd | 400.0007954 rd |
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 | rods | chains | rods |
---|---|---|---|
1 | ≈ 4.0000079535513 | 4 | ≈ 16.000031814205 |
1.5 | ≈ 6.0000119303269 | 4.5 | ≈ 18.000035790981 |
2 | ≈ 8.0000159071025 | 5 | ≈ 20.000039767756 |
2.5 | ≈ 10.000019883878 | 5.5 | ≈ 22.000043744532 |
3 | ≈ 12.000023860654 | 6 | ≈ 24.000047721308 |
The rod or perch or pole is a surveyors tool and unit of length equal to 5 1⁄2 yards, 16 1⁄2 feet, 1⁄320 of a statute mile or one-fourth of a surveyor's chain and 5.0292 meters.
Name of unit | Symbol | Definition | Relation to SI units | Unit System |
---|---|---|---|---|
rod | rd | ≡ 16 1⁄2 ft | = 5.0292 m | Imperial/US |
rods | chains | rods | chains |
---|---|---|---|
1 | ≈ 0.24999950290403 | 4 | ≈ 0.99999801161614 |
1.5 | ≈ 0.37499925435605 | 4.5 | ≈ 1.1249977630682 |
2 | ≈ 0.49999900580807 | 5 | ≈ 1.2499975145202 |
2.5 | ≈ 0.62499875726009 | 5.5 | ≈ 1.3749972659722 |
3 | ≈ 0.7499985087121 | 6 | ≈ 1.4999970174242 |
chains | rods |
---|---|
1 | ≈ 4.0000080 |
0.2499995 | ≈ 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 …) |