Convert length and distance units — meters, feet, inches, kilometers, miles, light years and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 ftm | 9.09091e-05 chain | |
| 0.01 ftm | 0.000909091 chain | |
| 0.1 ftm | 0.00909091 chain | |
| 1 ftm | 0.0909091 chain | |
| 5 ftm | 0.454545 chain | |
| 10 ftm | 0.909091 chain | |
| 50 ftm | 4.54545 chain | |
| 100 ftm | 9.09091 chain | |
| 1000 ftm | 90.9091 chain |
Multiply the number of Fathoms by 0.0909091 to get Chains. Formula: chain = ftm × 0.0909091. Example: 10 ftm × 0.0909091 = 0.909091 chain. To reverse, divide Chains by 0.0909091 to get Fathoms.
| Fathom (ftm) | Chain (chain) |
|---|---|
| 0.001 ftm | 9.09091e-05 chain |
| 0.01 ftm | 0.000909091 chain |
| 0.1 ftm | 0.00909091 chain |
| 0.5 ftm | 0.0454545 chain |
| 1 ftm | 0.0909091 chain |
| 2 ftm | 0.181818 chain |
| 5 ftm | 0.454545 chain |
| 10 ftm | 0.909091 chain |
| 20 ftm | 1.81818 chain |
| 50 ftm | 4.54545 chain |
| 100 ftm | 9.09091 chain |
| 250 ftm | 22.7273 chain |
| 500 ftm | 45.4545 chain |
| 1000 ftm | 90.9091 chain |
| 10000 ftm | 909.091 chain |
To convert Fathom to Chain, multiply by 0.0909091. Example: 10 ftm = 0.909091 chain
To convert Chain back to Fathom, divide by 0.0909091 (multiply by 11). Use the swap button above.
Start with 100 Fathoms = 9.09091 chain as your reference point. Scale up or down from there.
Coastal surveys record land dimensions in chains and water depths in fathoms. Surveyors producing integrated coastal zone management maps convert between the two units when merging land and hydrographic survey data.
Original harbour construction drawings used chains for land-side dimensions and fathoms for water depth. Engineers restoring Victorian harbours convert between the two units using original survey records.
Port engineers specifying berth dimensions use chains for quay lengths (based on land survey) and fathoms for alongside depth — both units appear in the same berth specification document requiring conversion.
Historic fishing rights defined by both shore distance in chains and water depth in fathoms require cross-unit conversion when legal disputes reference original survey documents from different measurement traditions.
Long-distance coastal footpaths in the UK cross both land (surveyed in chains) and tidal foreshore (charted in fathoms). Route planners convert between the two units when producing accurate distance guides.
Underwater archaeologists coordinate site positions using fathoms for depth while referencing onshore features from Ordnance Survey maps in chains — field reports require conversion between the two legacy imperial units.
The Fathom is a unit of Length measurement (symbol: ftm). 1 ftm = 0.0909091 chain. Used in scientific and practical Length measurement applications.
The Chain is a unit of Length measurement (symbol: chain). It is part of an internationally recognised measurement system used alongside the Fathom.
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 — from the idea of plumbing the depths. Despite metrication, fathoms remain on admiralty charts and in nautical tradition worldwide.
Edmund Gunter invented the surveyor's chain in 1620. His design — 100 links totalling exactly 66 feet — was brilliantly chosen: 10 chains × 10 chains = 1 acre, making area calculation trivially simple in the field. 80 chains = 1 mile, 10 chains = 1 furlong. The chain became standard across the British Empire and is written into American law — the US Public Land Survey System still divides land using chains and links.
Common use: Fathom to Chain conversion is needed when working with international standards, scientific publications, or reference materials that use different unit systems for Length measurement.