Convert Fathom to Rod
Convert fathoms to rods instantly. 1 fathom = 0.3636363636 rod — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Rod to Fathom converter for the reverse conversion.
Units explained
Fathom
A fathom is an Imperial unit of length equal to 6 feet or exactly 1.8288 meters. It is used almost exclusively for measuring water depth in maritime contexts.
The fathom derives from the Old English word fæthm, meaning "the embracing arms" — the distance between the fingertips of a person's outstretched arms. Standardized at 6 feet in English maritime tradition.
Fathoms are used in nautical depth charts, scuba diving, oceanography, and maritime literature. Despite metrication efforts, fathoms remain common in English-language nautical charts and recreational diving.
Old English origin (predating 1066); standardized at 6 feet by English maritime tradition; fixed at 1.8288 m exactly via the 1959 International Yard and Pound Agreement.
Rod
A rod is an Imperial unit of length equal to 16.5 feet (about 5.03 m). It is also called a perch or pole. Used historically in English and American land surveying.
The rod derives from medieval English land-surveying practice. Standardised at 16.5 feet (= 25 links of a surveyor's chain = 1/4 chain) by Edmund Gunter in 1620.
Rods are the standard unit in legacy US public-land-survey records, where lot dimensions are typically expressed in rods and chains. Modern surveyors generally use feet or meters but legacy deeds remain in rods.
Defined by Edmund Gunter in 1620 as 16.5 feet via the chain-based survey system; became exact via the 1959 International Yard and Pound Agreement.
Fathom to Rod conversion formula
The relationship between fathoms and rods:
To convert fathoms to rods, multiply the value in fathoms by 0.3636363636. To reverse, multiply rods by 2.75.
How to use this converter
Type a value into the calculator. The result in rods updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Rod to Fathom converter for the reverse direction.
Step-by-step: convert fathoms to rods
- Write down the value in fathoms (ftm).
- Multiply that value by the factor 0.3636363636.
- The product is the equivalent value in rods (rd).
- To reverse, multiply the rod value by 2.75.
Worked examples
Example 1 — Convert 1 ftm to rd:
1 × 0.3636363636 = 0.3636363636 rd
Example 2 — Convert 100 ftm to rd:
100 × 0.3636363636 = 36.3636363636 rd
Real-world example — Reference scenario in case of fallback
Conversion between human-scale length units is the everyday workflow of architecture, athletics, and apparel design — three of the most common contexts that span metric and imperial systems.
1 ftm × 0.3636363636 = 0.3636363636 rd
Real-world example — Adult height conversion
A 1.8-fathom-tall person measures a value in rods that converts the height to the unit favoured by American forms, schools, or driver's licences. This is daily routine for anyone living between metric and imperial systems.
1.8 ftm × 0.3636363636 = 0.6545454545 rd
Real-world example — Fabric purchase length
Two fathoms of fabric equals a value in rods essential for tailors and textile buyers sourcing material from international suppliers that quote in different units.
2 ftm × 0.3636363636 = 0.7272727273 rd
Fathom to Rod conversion table
Standard reference values for converting fathoms to rods:
| Fathom [ftm] | Rod [rd] |
|---|---|
| 0.01 | 0.0036363636 |
| 0.1 | 0.0363636364 |
| 1 | 0.3636363636 |
| 2 | 0.7272727273 |
| 3 | 1.0909090909 |
| 4 | 1.4545454545 |
| 5 | 1.8181818182 |
| 10 | 3.6363636364 |
| 20 | 7.2727272727 |
| 30 | 10.9090909091 |
| 40 | 14.5454545455 |
| 50 | 18.1818181818 |
| 100 | 36.3636363636 |
| 500 | 181.8181818182 |
| 1000 | 363.6363636364 |
Frequently asked questions
How many rods is 1 fathom?
How do I convert fathoms to rods?
How do I convert rods back to fathoms?
How many rods is 100 fathoms?
Popular length unit conversions
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Metric / SI (7 units)
Imperial / US Customary (26 units)
Nautical (1 units)
Sources & references
Conversion factor (1 ftm = 0.3636363636 rd) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.