How many fathoms are in 1 chain?

One chain equals exactly 11 fathoms. This clean ratio exists because both are defined in feet: 1 chain = 66 feet, 1 fathom = 6 feet, and 66/6 = 11.

How do I convert chains to fathoms?

Multiply the number of chains by 11. For example, 5 chains = 55 fathoms. The conversion is exact with no rounding needed.

Are chains and fathoms related historically?

Both derive from the English foot-based measurement system. The chain was designed for land surveying (66 feet = 4 rods), while the fathom was designed for measuring water depth (the span of outstretched arms, roughly 6 feet). They share the foot as their common ancestor.

Chains to Fathoms (ch to ftm) Converter

1 ch = 11 ftm

1 Chain equals 11 Fathoms (1 ch = 11 ftm). Convert Chains to Fathoms with formula, table, and examples.

One chain equals exactly 11 fathoms. Both units come from the English measurement tradition: the chain (66 feet) for land surveying and the fathom (6 feet) for maritime depth. The clean ratio of 11:1 reflects their shared heritage in the English foot system.

How to Convert Chains to Fathoms

ftm = ch × 11

Multiply the value in Chains by 11

Take your value in Chains
Multiply by 11
Read the result in Fathoms

Common Chains to Fathoms Conversions

Chains (ch)	Fathoms (ftm)	Status
0.1 ch	1.1 ftm
0.25 ch	2.75 ftm
0.5 ch	5.5 ftm
1 ch	11 ftm
2 ch	22 ftm
5 ch	55 ftm
10 ch	110 ftm
20 ch	220 ftm
40 ch	440 ftm
80 ch	880 ftm
100 ch	1,100 ftm
200 ch	2,200 ftm
500 ch	5,500 ftm
1,000 ch	11,000 ftm

Good to Know About Chains to Fathoms Conversion

The chain and fathom both emerged from the same English measurement tradition but diverged into different domains: land and sea. Their 11:1 ratio is a remnant of the coherent imperial system where all units were defined in feet.

Chains to Fathoms: What You Need to Know

Since 1 chain = 66 feet and 1 fathom = 6 feet, the ratio is exactly 66/6 = 11. Ten chains (1 furlong) equals 110 fathoms. This is one of the few chain conversions that yields a clean whole number, thanks to both units being defined as exact multiples of the foot.

What is a Chain? ch

Exactly 66 feet or 4 rods (20.1168 m). Invented by Edmund Gunter for land surveying. 80 chains make one mile. Still used in US public land surveys.

Imperial land surveying US public land

Learn more about Chain →

What is a 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.

Imperial water depth nautical marine charts

Learn more about Fathom →

Going the other way? Use our Fathoms to Chains converter.

Chains to Fathoms FAQ

One chain equals exactly 11 fathoms. This clean ratio exists because both are defined in feet: 1 chain = 66 feet, 1 fathom = 6 feet, and 66/6 = 11.
Multiply the number of chains by 11. For example, 5 chains = 55 fathoms. The conversion is exact with no rounding needed.
Both derive from the English foot-based measurement system. The chain was designed for land surveying (66 feet = 4 rods), while the fathom was designed for measuring water depth (the span of outstretched arms, roughly 6 feet). They share the foot as their common ancestor.

Non-Frequently Asked Questions About Chains to Fathoms

Questions nobody should ask - but someone did.

Technically a chain is 11 fathoms, so you could lower one into water and count. But sailors used lead lines, not 20-meter metal chains. A chain sinking to the bottom would be hard to retrieve and terrible for your back.