Rope to Fathom Conversion Calculator: Free Online Tool
Convert ropes to fathoms with our free online length converter.
Rope to Fathom Calculator
How to Use the Calculator:
- Enter the value you want to convert in the 'From' field (Rope).
- The converted value in Fathom will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Length category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Rope to Fathom
Converting Rope to Fathom involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Rope = 3.333333 fathomsExample Calculation:
Convert 10 ropes: 10 × 3.333333 = 33.33333 fathoms
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
What is a Rope and a Fathom?
The Rope is an historical English unit of length, primarily used in surveying and sometimes in building or architecture. Its length was typically defined as 20 feet.
This equates to:
- 6.096 meters (m)
- Approximately 6.67 yards (yd)
Unlike more standardized surveying units like the chain, the rope's length could sometimes vary by region or specific use, but 20 feet is the most commonly cited value.
The Fathom (symbol fath) is a unit of length in the imperial and U.S. customary systems of measurement, defined as exactly 6 feet (ft). This is equivalent to 2 yards or 1.8288 meters (m). It is almost exclusively used in maritime contexts for measuring the depth of water.
Note: The Rope is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Fathom belongs to the imperial/US customary system.
History of the Rope and Fathom
The origin of the Rope unit likely stems directly from the use of actual ropes of a predetermined length for measuring land or distances in medieval England and potentially earlier. Before the widespread adoption of more durable and precise measuring tools like metal chains (such as Gunter's chain, introduced in the 17th century), knotted or marked ropes served as practical, albeit less accurate, instruments for surveyors.
The length of 20 feet provided a convenient measure for certain types of land division or construction layout. However, ropes were susceptible to stretching, shrinking (when wet), and wear, leading to inconsistencies. This lack of precision contributed to its gradual replacement by the rod (16.5 feet) and the chain (66 feet) for official surveying work. The Rope unit fell into obsolescence as measurement standards became more rigorous and legally defined.
The word "fathom" originates from the Old English word fæthm, meaning "a pair of outstretched arms" or "embrace". Historically, the length was derived from the distance between the fingertips of a man's outstretched arms, a practical method for sailors measuring the length of a sounding line (a rope with a weight used to measure water depth) as they hauled it in. This naturally variable measure was eventually standardized to precisely 6 feet. For centuries, it was the primary unit for depth soundings on nautical charts and in maritime operations in English-speaking countries and beyond. While its official use has declined with metrication, it remains a significant unit in nautical tradition.
Common Uses for ropes and fathoms
Explore the typical applications for both Rope (imperial/US) and Fathom (imperial/US) to understand their common contexts.
Common Uses for ropes
The Rope is now an obsolete unit, but historically it was used for:
- Land Surveying: Measuring property boundaries, fields, and plots of land, particularly in older or less formal surveys.
- Building and Construction: Laying out foundations or measuring lengths in large-scale construction projects in historical contexts.
- Agriculture: Estimating field sizes or row lengths.
- Nautical Measurement (Less Common): Occasionally, "rope" might refer to specific lengths used on ships, but this is distinct from the land surveying unit and often context-dependent (similar to a "cable length").
Common Uses for fathoms
The fathom's use is strongly tied to the sea:
- Hydrography & Navigation: Measuring water depth (soundings) on nautical charts. Many charts, particularly older ones or those used in the US and UK, still use fathoms. Contour lines showing seabed depth are often called "fathom lines".
- Nautical Terminology: Used historically to measure the length of ropes and anchor cables (e.g., a "cable length" was often defined as 100 or 120 fathoms).
- Commercial Fishing: Sometimes used by fishermen to describe the length of nets or fishing lines, or the depth at which they are fishing.
- Literature & Figurative Language: Frequently appears in maritime literature (e.g., "full fathom five" from Shakespeare's The Tempest). Metaphorically, "to fathom" means to comprehend or get to the bottom of something complex.
- Historical Land Measurement: Very occasionally used in historical land surveying or mining contexts, but this was rare compared to its maritime use.
Frequently Asked Questions
Questions About Rope (rope)
How long is a Rope?
The most common definition for the historical English Rope unit is 20 feet, which is exactly 6.096 meters.
How does the Rope compare to other surveying units?
- Rod (or Pole, Perch): 1 Rod = 16.5 feet. Therefore, 1 Rope ≈ 1.21 Rods.
- Gunter's Chain: 1 Chain = 66 feet = 4 Rods. Therefore, 1 Chain = 3.3 Ropes.
- Foot: 1 Rope = 20 feet.
- Yard: 1 Rope ≈ 6.67 yards.
Was the Rope a standardized unit?
No, it was not rigorously standardized like later units such as the foot or the Gunter's chain. While 20 feet was a common value, variations could exist, and the physical nature of a rope made it inherently less precise than metal instruments.
Is the Rope unit still used today?
No, the Rope as a formal unit of length is obsolete. Modern surveying uses meters, feet, and occasionally chains or rods in specific legal contexts (like older land deeds in the US), but not the Rope.
Is the Rope an SI unit?
No, the Rope is not an SI unit. It is a traditional English unit. The SI base unit for length is the meter (m).
About Fathom (fath)
How many feet are in a fathom?
There are exactly 6 feet (ft) in 1 fathom.
How many meters are in a fathom?
One fathom is equal to exactly 1.8288 meters (m).
Is the fathom an SI unit?
No, the fathom is not an SI unit. It is part of the imperial and U.S. customary systems. The corresponding SI unit for length is the meter (m).
Is the fathom still commonly used today?
Its usage has decreased significantly due to the widespread adoption of the metric system in international shipping and hydrography. However, it remains common on nautical charts produced by countries like the United States and the United Kingdom, and it persists in recreational boating, commercial fishing communities, maritime tradition, and literature. Modern international charts increasingly use meters for depth soundings.
Where does the word 'fathom' come from?
The word originates from the Old English fæthm, which referred to the span of a person's outstretched arms. This distance was the practical basis for the original measurement used by sailors.
Conversion Table: Rope to Fathom
| Rope (rope) | Fathom (fath) |
|---|---|
| 1 | 3.333 |
| 5 | 16.667 |
| 10 | 33.333 |
| 25 | 83.333 |
| 50 | 166.667 |
| 100 | 333.333 |
| 500 | 1,666.667 |
| 1,000 | 3,333.333 |
All Length Conversions
Other Units from Length
- Meter (m)
- Kilometer (km)
- Hectometer (hm)
- Decimeter (dm)
- Centimeter (cm)
- Millimeter (mm)
- Inch (in)
- Foot (ft)
- Yard (yd)
- Mile (mi)
- Nautical Mile (NM)
- Micrometer (μm)
- Nanometer (nm)
- Light Year (ly)
- Astronomical Unit (AU)
- Parsec (pc)
- Angstrom (Å)
- Point (Typography) (pt)
- Mil/Thou (mil)
- Furlong (fur)
- Link (Gunter's) (li)
- Pace (pace)
- Span (span)
- Digit (digit)
- Cable Length (cb)
- Ell (ell)
- Finger (finger)
- Roman Mile (m.p.)
- Stadion (stadion)
- Chi (Chinese) (chi)
- Shaku (Japanese) (shaku)
- Li (Chinese) (li)
- Toise (toise)
- Bolt (bolt)
- Smoot (smoot)
- Sajene (sajene)
- Ken (ken)
- Wa (wa)
- Vara (vara)
- Aln (aln)
- Cubit (Royal/Egyptian) (cubit)
- Versta (versta)
- Arpent (arpent)
- Ri (Japanese) (ri)
- Klafter (klafter)
- Yojana (yojana)
- Skein (skein)