How many AU is 1 fathom?

One fathom equals approximately 1.222 x 10-11 AU. A fathom is about 12 trillionths of an AU.

How many fathoms are in 1 AU?

One AU contains approximately 8.181 x 1010 fathoms (about 81.8 billion fathoms).

Is this conversion useful?

No. Fathoms measure ocean depths from 0 to about 6,000. AU measures planetary distances. The entire ocean depth is an infinitesimal fraction of 1 AU.

Fathoms to Astronomical Units (ftm to au) Converter

1 ftm = 1.22248 × 10⁻¹¹ au

1 Fathom equals 1.22248 × 10⁻¹¹ Astronomical Units (1 ftm = 1.22248 × 10⁻¹¹ au). Convert Fathoms to Astronomical Units with formula, table, and examples.

One fathom equals approximately 1.222 x 10^-11 astronomical units. The deepest ocean trench (about 6,000 fathoms) is only 7.3 x 10^-8 AU below sea level. The fathom measures maritime depth; the AU measures the Earth-Sun distance. No oceanographer has ever expressed depth in AU.

How to Convert Fathoms to Astronomical Units

au = ftm × 1.22248 × 10⁻¹¹

Multiply the value in Fathoms by 1.22248 × 10⁻¹¹

Take your value in Fathoms
Multiply by 1.22248 × 10⁻¹¹
Read the result in Astronomical Units

Common Fathoms to Astronomical Units Conversions

Fathoms (ftm)	Astronomical Units (au)	Status
1 ftm	1.22248 × 10⁻¹¹ au
10 ftm	1.22248 × 10⁻¹⁰ au
100 ftm	1.22248 × 10⁻⁹ au
1,000 ftm	1.22248 × 10⁻⁸ au
10,000 ftm	1.22248 × 10⁻⁷ au
100,000 ftm	0.000001 au
1,000,000 ftm	0.00001 au
10,000,000 ftm	0.0001 au
100,000,000 ftm	0.0012 au

Good to Know About Fathoms to Astronomical Units Conversion

The entire depth of the ocean from surface to trench bottom is only 0.0000073% of the Earth-Sun distance. If the AU were a football field, the ocean would be thinner than a sheet of paper laid on the goal line.

Fathoms to Astronomical Units: What You Need to Know

The Earth-Sun distance (1 AU) would be about 81.8 billion fathoms of water depth if such a thing existed. The Mariana Trench at 6,011 fathoms is barely 0.0000073% of an AU. These numbers show how the entire ocean is a thin film on the astronomical scale.

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 →

What is a Astronomical Unit? au

Exactly 149,597,870,700 meters by IAU 2012 definition. Roughly the average distance from the Earth to the Sun. Used for distances within our solar system.

Astronomical solar system distances astronomy planetary science

Learn more about Astronomical Unit →

Going the other way? Use our Astronomical Units to Fathoms converter.

Fathoms to Astronomical Units FAQ

One fathom equals approximately 1.222 x 10^-11 AU. A fathom is about 12 trillionths of an AU.
One AU contains approximately 8.181 x 10¹⁰ fathoms (about 81.8 billion fathoms).
No. Fathoms measure ocean depths from 0 to about 6,000. AU measures planetary distances. The entire ocean depth is an infinitesimal fraction of 1 AU.

Non-Frequently Asked Questions About Fathoms to Astronomical Units

Questions nobody should ask - but someone did.

The Sun is 1 AU = about 8.178 x 10¹⁰ fathoms away. The actual ocean is only about 6,000 fathoms deep at its maximum. You would need to stack about 13.6 million Mariana Trenches to reach the Sun. The ocean is deep but not that deep.
At a typical submarine descent rate of about 5 fathoms per minute, reaching 8.178 x 10¹⁰ fathoms would take about 31 million years. Pack a very large lunch.
Saying 'the Sun is 82 billion fathoms away' does sound more ominous than '1 AU.' But astronomers prefer compact numbers. Nobody writes scientific papers in fathoms. The drama is not worth the extra zeros.