How many feet are in a fathom?

The modern/common fathom is 6 feet. However, the Admiralty fathom was 6.08 feet. This tool supports both definitions.

How do you convert fathoms to feet?

Multiply fathoms by the chosen fathom length. For the 6 ft fathom: feet = fathoms × 6. For the 6.08 ft Admiralty fathom: feet = fathoms × 6.08.

Yes. Divide feet by the fathom length you are using. For example, 24 ft ÷ 6 ft/fathom = 4 fathoms.

Reverse: Feet → Fathoms

Feet

Convert an existing feet depth

Fathoms

fathoms = feet ÷ factor

Current definition: 6 ft per fathom

Make sure this matches the chart, sailing directions, or historical source you’re using.

Quick table

Fathoms	Feet (6 ft)	Feet (6.08 ft)	Notes
1	6.00	6.08	Single fathom
2	12.00	12.16	Shallow soundings
5	30.00	30.40	Common berth depth
10	60.00	60.80	Anchor depths
20	120.00	121.60	Deeper approaches

Most modern nautical and diving references assume 1 fathom = 6 feet. This comes from the idea of a “fathom” being the span of outstretched arms.

Historically, there were small variations — for example the Admiralty fathom of 6.08 ft. That’s why this page gives you multiple presets.

feet = fathoms × fathom_length

Standard: feet = fathoms × 6

Admiralty: feet = fathoms × 6.08

fathoms = feet ÷ fathom_length

Example: 48 ft ÷ 6 = 8 fathoms

If your chart or document doesn’t say otherwise, use 6 ft. If you are checking older British naval material, try 6.08 ft.

First convert to feet, then multiply by 0.3048. Example: 5 fathoms × 6 ft/fathom = 30 ft. 30 ft × 0.3048 = 9.144 m.

Because different navies and periods standardized slightly different lengths. Today, 6 ft is the simplest and most common.