Fathoms to Inches (ftm to in)

1 fathom equals 72 inches exactly.

1 fathom = 72 inches

How to convert fathoms to inches

To convert fathoms to inches, multiply the number of fathoms by 72. This factor is exact. To go the other way, multiply inches by 0.01388888889 (rounded).

inches = fathoms × 72

Example: 10 fathoms = 720 inches.

About these units

Fathom (ftm)

NauticalTraditional unit (still used in some regions)

6 feet (1.8288 m), traditionally the span of a man's outstretched arms. Still used for water depth on nautical charts in some countries.

Old English fæðm meant a pair of outstretched arms, and the word gave English its fathom. That is the origin of the measure: the span between the fingertips of a man with his arms spread wide, roughly the height of a person. Because bodies differ, the fathom was not fixed for centuries. Merchant ships are recorded as using about five and a half feet, and fishing boats five or seven, until the length was settled at six feet in the nineteenth century.

Sailors counted in fathoms because a hand sounding line carried marks at fathom intervals, so the depth could be read off when the weight touched bottom. Water shallower than 100 fathoms was said to be in soundings. Anchor chain and fishing line were also sold and counted in fathoms. The figure used here is exactly six feet, or 1.8288 m, which makes two yards one fathom. Most charts today show metres, though some national charts still print fathoms.

1 fathom = 1.8288 meters (exactly).

Sources: Wikipedia: Fathom; NIST SP 811, Appendix B.8 (length conversion factors)

Inch (in)

US & ImperialCurrent unit

1/12 of a foot. Defined as exactly 25.4 millimeters since 1959, when the US and Commonwealth countries agreed a common international inch.

Latin uncia, meaning one-twelfth, is the root of both inch and ounce, and it passed into Old English as ynce. Roman measurers divided their foot into twelve unciae, and the English inch kept that twelfth. After 1066 an inch was reckoned as three barleycorns, and a 1324 statute attributed to Edward II spelled out the definition as three grains of barley, dry and round, placed end to end lengthwise. For centuries the inch was simply a twelfth of a foot, or a thirty-sixth of a yard, and the US and UK each kept their own copy of the standard yard.

Those copies differed slightly until the 1959 international agreement fixed the yard at exactly 0.9144 meter, which made the inch exactly 25.4 millimeters. The US adopted it in 1959 and the UK ratified it in 1963, effective 1964. Today the inch is still the customary unit in the United States and Canada, and the UK keeps it on road signs. Worldwide it also names display diagonals, wheel rims, tire codes and pipe sizes.

1 inch = 0.0254 meters (exactly).

Sources: Wikipedia: Inch; Wikipedia: Yard; NIST Guide to the SI, Appendix B.8: conversion factors

Related conversions

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