# Feet to Fathoms (ft to ftm)

Source: https://www.unitconvertercalculator.com/length/feet-to-fathoms/

**1 ft = 0.16666666666667 ftm**

One foot equals exactly 1/6 of a fathom, or approximately 0.1667 fathoms. Six feet make exactly one fathom. The foot is the everyday American unit; the fathom is the traditional maritime depth unit. Their 6:1 ratio derives from the fathom being defined as a man's arm span (about 6 feet).

## Formula

Convert Feet to Fathoms

## Conversion Table

| Feet (ft) | Fathoms (ftm) |
|---|---|
| 0.5 ft | 0.083333333333333 ftm |
| 1 ft | 0.16666666666667 ftm |
| 2 ft | 0.33333333333333 ftm |
| 3 ft | 0.5 ftm |
| 5 ft | 0.83333333333333 ftm |
| 6 ft | 1 ftm |
| 10 ft | 1.6666666666667 ftm |
| 12 ft | 2 ftm |
| 20 ft | 3.3333333333333 ftm |
| 50 ft | 8.3333333333333 ftm |
| 100 ft | 16.666666666667 ftm |
| 500 ft | 83.333333333333 ftm |
| 1000 ft | 166.66666666667 ftm |
| 5280 ft | 880 ftm |

## Units

### Foot (ft)

An imperial unit of length equal to 12 inches or 0.3048 meters. Used in the US and UK for height, altitude, and construction.

### Fathom (ftm)

Exactly 6 feet (1.8288 m). Traditionally used to measure water depth in nautical contexts. Originally based on the span of outstretched arms.

## Background

A 30-foot depth is 5 fathoms (Shakespeare's 'full fathom five'). A 100-foot depth is about 16.67 fathoms. A recreational dive limit of 130 feet is about 21.67 fathoms. Divers who learned depth in feet can convert to the fathom soundings shown on older nautical charts by dividing by 6.

## Good to Know

The fathom (6 feet) and the foot (1 foot) are both body-based units: the fathom from arm span, the foot from foot length. The 6:1 ratio reflects human proportions: your arm span is roughly 6 times your foot length.

## FAQ

### How many fathoms is 1 foot?

One foot equals exactly 1/6 of a fathom (approximately 0.1667 fathoms). Six feet make one fathom.

### How do I convert feet to fathoms?

Divide the foot value by 6. For example, 42 feet = 7 fathoms. For 50 feet: 50/6 = 8.33 fathoms.

### Why is 1 fathom 6 feet?

The fathom was originally the span of a man's outstretched arms, which averages about 6 feet. This body-based measurement was standardized at exactly 6 feet centuries ago.

## Non-Frequently Asked Questions

### Am I tall enough to be a fathom?

A fathom is 6 feet. If you are exactly 6 feet tall, you ARE one fathom. About 14.5% of American men are 6 feet or taller. So about one in seven American men is at least one fathom tall. The rest of us fall short of our nautical potential.

### Why did 'mark twain' sound better than 'two fathoms'?

On the Mississippi, leadsmen called out depth: 'mark twain' meant 2 fathoms (12 feet) - safe water. It was shorter, punchier, and easier to hear over engine noise than 'two fathoms.' Samuel Clemens chose it as his pen name because it sounded authoritative. Branding matters.

### If I am 5 feet 10 inches, what fraction of a fathom am I?

Five feet 10 inches = 70 inches = 5.833 feet. A fathom is 6 feet. So you are 0.972 fathoms, or 97.2% of a fathom. You are almost exactly one fathom. Close enough for literature, too short for the NBA.

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## See Also

- [Fathoms to Feet](https://www.unitconvertercalculator.com/length/fathoms-to-feet/)