Convert length and distance units — meters, feet, inches, kilometers, miles, light years and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 nmi | 1.01269 ftm | |
| 0.01 nmi | 10.1269 ftm | |
| 0.1 nmi | 101.269 ftm | |
| 1 nmi | 1012.69 ftm | |
| 5 nmi | 5063.43 ftm | |
| 10 nmi | 10126.9 ftm | |
| 50 nmi | 50634.3 ftm | |
| 100 nmi | 101269 ftm | |
| 1000 nmi | 1.01269e+06 ftm |
Multiply the number of Nautical Miles by 1012.69 to get Fathoms. Formula: ftm = nmi × 1012.69. Example: 10 nmi × 1012.69 = 10126.9 ftm. To reverse, divide Fathoms by 1012.69 to get Nautical Miles.
| Nautical Mile (nmi) | Fathom (ftm) |
|---|---|
| 0.001 nmi | 1.01269 ftm |
| 0.01 nmi | 10.1269 ftm |
| 0.1 nmi | 101.269 ftm |
| 0.5 nmi | 506.343 ftm |
| 1 nmi | 1012.69 ftm |
| 2 nmi | 2025.37 ftm |
| 5 nmi | 5063.43 ftm |
| 10 nmi | 10126.9 ftm |
| 20 nmi | 20253.7 ftm |
| 50 nmi | 50634.3 ftm |
| 100 nmi | 101269 ftm |
| 250 nmi | 253171 ftm |
| 500 nmi | 506343 ftm |
| 1000 nmi | 1012690 ftm |
| 10000 nmi | 10126900 ftm |
To convert Nautical Mile to Fathom, multiply by 1012.69. Example: 10 nmi = 10126.9 ftm
To convert Fathom back to Nautical Mile, divide by 1012.69 (multiply by 0.000987473). Use the swap button above.
Start with 100 Nautical Miles = 101269 ftm as your reference point. Scale up or down from there.
Classic nautical charts show horizontal distances in nautical miles and water depths in fathoms. Every mariner who navigates with traditional charts converts between nautical miles (position) and fathoms (depth) in every passage plan.
Safe anchoring requires enough rode for the water depth. Mariners use fathoms for depth and estimate rode length in relation to nautical miles sailed — calculating anchor scope is a daily nmi-to-fathom conversion for cruising sailors.
Traditional fishing ground records describe location in nautical miles from port and fishing depth in fathoms. Fishermen and fleet managers reference both units when planning fishing trips to traditional grounds.
Royal Navy logbooks record passage distances in nautical miles and soundings in fathoms. Naval historians and archivists routinely convert between the two when cross-referencing voyage logs with hydrographic survey records.
Submarine navigators track horizontal position in nautical miles while managing depth in fathoms from operational depth charts — both units are active simultaneously in submarine tactical navigation.
Navigation students learn to work with nautical miles for distance and fathoms for depth simultaneously — converting between the two is a core competency in both UK and US maritime academy training programmes.
The Nautical Mile is a unit of Length measurement (symbol: nmi). 1 nmi = 1012.69 ftm. Used in scientific and practical Length measurement applications.
The Fathom is a unit of Length measurement (symbol: ftm). It is part of an internationally recognised measurement system used alongside the Nautical Mile.
The nautical mile was defined by Earth's own geometry — one minute of arc of latitude along a meridian, approximately 1,852 metres. This elegant definition made it perfect for navigation: on any nautical chart, one nautical mile equals exactly one arcminute, allowing direct distance measurement with dividers without any conversion. The unit was used informally by mariners for centuries before the International Hydrographic Conference standardised it at exactly 1,852 metres in 1929. Today it is universally used in maritime and international aviation — the only two domains that never adopted kilometres for operational distances, largely because the geometric relationship to Earth's circumference remains too useful to abandon.
The fathom derives from the Old English 'fæthm', meaning the span of outstretched arms — roughly 6 feet or 1.8 metres. It was the primary depth measurement unit used by mariners for millennia, recorded in the Bible and used by ancient Greeks. The word 'fathom' also entered English as a verb meaning to understand something deeply. Despite metrication, fathoms remain on admiralty charts worldwide.
Common use: Nautical Mile to Fathom conversion is needed when working with international standards, scientific publications, or reference materials that use different unit systems for Length measurement.