Fathom to Aln Conversion Calculator: Free Online Tool
Convert fathoms to alnar with our free online length converter.
Fathom to Aln Calculator
How to Use the Calculator:
- Enter the value you want to convert in the 'From' field (Fathom).
- The converted value in Aln 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 Fathom to Aln
Converting Fathom to Aln involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Fathom = 3.078788 alnar
Example Calculation:
Convert 10 fathoms: 10 × 3.078788 = 30.78788 alnar
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.
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What is a Fathom and a Aln?
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.
The Aln (Swedish), Alen (Danish and Norwegian) was a traditional Scandinavian unit of length, analogous to the English ell or cubit. Its length varied significantly by region and time but was generally based on the length of the forearm.
Key standardized or common values include:
- Swedish Aln: Officially standardized (as the Rydaholmsaln) in 1665 and confirmed in 1735 as exactly 2 Swedish fot (feet). This equates to approximately 0.5938 meters (or 59.38 cm / 23.38 inches).
- Danish Alen: The common standard (Sjællandsk alen) was 2 Danish fod (feet), equating to approximately 0.6277 meters (or 62.77 cm / 24.71 inches).
- Norwegian Alen: Often followed the Danish standard due to political union. After 1824, it was legally defined as 2 Norwegian fot, equating to 0.6275 meters (or 62.75 cm / 24.70 inches), very close to the Danish value.
The Aln/Alen was typically subdivided into 4 kvarter (quarters).
Note: The Fathom is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Aln belongs to the imperial/US customary system.
History of the Fathom and Aln
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.
The Aln/Alen originates from the Proto-Germanic word for forearm (alinō), reflecting its basis as an anthropomorphic unit, similar to the cubit in other cultures. For centuries, its length was inconsistent, varying between regions, cities, and trades within Sweden, Denmark, and Norway.
- Early Variations: Numerous local standards existed, often based on physical rods kept by authorities or guilds.
- Standardization Efforts:
- Sweden: Attempts at standardization culminated in the adoption of the Rydaholmsaln (based on a specific iron standard bar from Rydaholm church) in 1665, defined as 2 fot. This standard (≈0.5938 m) became mandatory nationwide in 1735.
- Denmark & Norway: The Sjællandsk alen (Zealand ell, ≈0.6277 m) became the dominant standard in Denmark and, consequently, in Norway during their union. Norway later formally adopted a slightly different value (≈0.6275 m) based on its own fot definition in 1824.
- Metrication: The Aln/Alen was officially replaced by the metric system during the 19th and early 20th centuries: Norway in 1875, Sweden in 1889, and Denmark in 1907.
Common Uses for fathoms and alnar
Explore the typical applications for both Fathom (imperial/US) and Aln (imperial/US) to understand their common contexts.
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.
Common Uses for alnar
Historically, the Aln/Alen was a fundamental unit for everyday trade and craft:
- Textiles: Its most prominent use was measuring cloth (wool, linen, silk). Standardization was often driven by the textile trade.
- Timber and Lumber: Measuring lengths of wood.
- Rope and Cordage: Measuring lengths of rope.
- Construction: Used in building measurements, though perhaps less formally than in trade.
- General Trade: Measuring various goods sold by length.
It was less commonly used for land surveying, where units like the stång (rod) or mil (mile) were preferred.
Frequently Asked Questions
Questions 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.
About Aln (aln)
How long is an Aln/Alen?
There isn't one single value, as it depended on the country and era. The main official standards were:
- Swedish Aln: ~0.594 meters / ~23.4 inches
- Danish Alen: ~0.628 meters / ~24.7 inches
- Norwegian Alen: ~0.628 meters / ~24.7 inches (very close to Danish)
Always consider the context (Swedish, Danish, or Norwegian) when encountering this unit in historical documents.
What's the difference between the Aln in different countries?
The primary difference was length:
- The Swedish Aln (≈59.4 cm) was noticeably shorter than the Danish and Norwegian Alen (both ≈62.8 cm).
- All were typically defined as 2 local fot (feet), but the length of the fot itself varied between the countries.
Is the Aln related to the English Ell?
Yes, both the Aln/Alen and the English Ell are historical units of length derived from the concept of the cubit or forearm length (Latin ulna). However, their standardized lengths differed significantly. The most common English Ell was 45 inches (1.143 m), much longer than any standard Scandinavian Aln/Alen.
Is the Aln/Alen still used today?
No, the Aln/Alen is obsolete. It was officially replaced by the meter in Sweden, Denmark, and Norway during the metrication process in the late 19th and early 20th centuries. Its use today is purely historical.
Is the Aln an SI unit?
No, the Aln/Alen is not an SI unit. It is a traditional unit from the historical Scandinavian systems of measurement. The SI base unit for length is the meter (m).
Conversion Table: Fathom to Aln
Fathom (fath) | Aln (aln) |
---|---|
1 | 3.079 |
5 | 15.394 |
10 | 30.788 |
25 | 76.97 |
50 | 153.939 |
100 | 307.879 |
500 | 1,539.394 |
1,000 | 3,078.788 |
All Length Conversions
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