The US survey foot is 1200/3937 meters and is retained for legacy land records.
US survey feet to Fathoms Converter — ftUS to ftm
Convert US survey foot (ftUS) to Fathom (ftm) using the exact conversion factor (1 us survey foot = 0.166667 fathom). See the formula, worked examples, and conversion table.
US survey feet to Fathoms converter
Converter
Length Converter
Convert SI, imperial, US customary, astronomical, scientific, and historical length units.
Context values
Some unit families need one extra value for a physically accurate result.
A fathom is six feet.
Result = input x 0.3048006096 / 1.8288.
Length uses the meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting US survey feet to Fathoms
US survey foot and Fathom both measure length. Specifically: The US survey foot is 1200/3937 meters and is retained for legacy land records, and a fathom is six feet.
Formula
fathoms = us survey feet × 0.166667000001
This factor comes from each unit's defined relationship to the category's base unit: 1 us survey foot equals 0.304800609601 base units, and 1 fathom equals 1.8288 base units, so dividing one by the other gives the direct us survey foot-to-fathom factor of 0.166667000001.
Simple example
1 ftUS × 0.166667 = 0.166667 ftm
1 us survey foot = 0.166667 fathoms.
Real-world example
10 ftUS × 0.166667 = 1.66667 ftm
10 us survey feet = 1.66667 fathoms.
Conversion table
| US survey foot (ftUS) | Fathom (ftm) |
|---|---|
| 1 ftUS | 0.166667 ftm |
| 5 ftUS | 0.833335 ftm |
| 10 ftUS | 1.66667 ftm |
| 21.0975 ftUS | 3.516257033 ftm |
| 42.195 ftUS | 7.032514065 ftm |
| 100 ftUS | 16.6667 ftm |
Reverse conversion: Fathom to US survey foot
0.166667 ftm × 5.999988 = 1 ftUS
0.166667 fathoms = 1 us survey feet.
us survey feet = fathoms × 5.999988
For a page dedicated to this direction, see Fathom to US survey foot.
Understanding the US survey foot (ftUS)
The US survey foot is 1200/3937 meters and is retained for legacy land records.
Understanding the Fathom (ftm)
A fathom is six feet.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many fathoms are in 1 us survey foot?
1 us survey foot equals 0.166667 fathoms, using the exact defined conversion factor rather than an estimate.
How do I convert us survey foot to fathom?
Multiply the us survey foot value by 0.166667. The converter above does this instantly to whatever precision you set.
How do I convert fathom back to us survey foot?
Use the reverse factor: 1 fathom equals 5.999988 us survey feet. You can also use the swap control in the converter above to flip the direction instantly.
What is a us survey foot?
US survey foot (ftUS) is a unit of length.
What is a fathom?
Fathom (ftm) is a unit of length.
Is the us survey foot to fathom conversion exact?
Yes. Both us survey foot and fathom are defined by fixed standards rather than physical artifacts, so the factor of 0.166667 used above is exact to as many digits as you choose to display.