Convert Kilometer to Furlong
Convert kilometers to furlongs instantly. 1 kilometer = 4.9709695379 furlong — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Furlong to Kilometer converter for the reverse conversion.
Units explained
Kilometer
A kilometer is a metric unit of length equal to one thousand meters. It is the standard unit for measuring road distances, geographic distances, and other large-scale measurements in metric countries.
The kilometer was defined alongside the meter in 1795 using the standard SI prefix kilo- (from Greek chilioi, "thousand"), denoting one thousand units.
Kilometers are used worldwide (except the United States and a few others) for road signage, geographic distance, athletic events, and scientific distances at planetary scale. Speed limits in most countries are given in km/h.
Adopted 1795 in France as part of the original metric system; the kilometer became the global standard for road and geographic distance through the 19th and 20th century metric adoption.
Furlong
A furlong is an Imperial unit of length equal to 660 feet, or exactly one eighth of a mile (about 201.17 m). It is the longest unit in the traditional English farm-and-survey system.
The furlong derives from Old English furh (furrow) + lang (long) — originally the length of a furrow in a typical medieval English open field. Standardised at 660 feet (= 10 chains = 220 yards = 1/8 mile) in medieval times.
Furlongs are the standard distance unit in horse racing (e.g., 'The race is 8 furlongs'), historical English farming and surveying, and occasional poetic or rhetorical usage. Modern racing courses worldwide list distances in furlongs.
Medieval English farming origin; standardised at 660 feet; remains the official distance unit in flat-racing thoroughbred horse races worldwide.
Kilometer to Furlong conversion formula
The relationship between kilometers and furlongs:
To convert kilometers to furlongs, multiply the value in kilometers by 4.9709695379. To reverse, multiply furlongs by 0.201168.
How to use this converter
Type a value into the calculator. The result in furlongs updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Furlong to Kilometer converter for the reverse direction.
Step-by-step: convert kilometers to furlongs
- Write down the value in kilometers (km).
- Multiply that value by the factor 4.9709695379.
- The product is the equivalent value in furlongs (fur).
- To reverse, multiply the furlong value by 0.201168.
Worked examples
Example 1 — Convert 1 km to fur:
1 × 4.9709695379 = 4.9709695379 fur
Example 2 — Convert 100 km to fur:
100 × 4.9709695379 = 497.0969537899 fur
Real-world example — Maritime exclusion zone
A 200-kilometer exclusion zone (a common maritime boundary) converts to a different value in furlongs that's useful when describing the same zone in everyday land-distance units.
200 km × 4.9709695379 = 994.1939075797 fur
Real-world example — Coastal cruise distances
A 10-kilometer coastal sailing route converts to a different value in furlongs — useful for cruise operators who switch between maritime, aviation, and road-distance units depending on the leg of the trip.
10 km × 4.9709695379 = 49.709695379 fur
Real-world example — Road-sign distances across systems
A 100-kilometer road sign converts cleanly into furlongs — exactly the conversion drivers planning trips abroad rely on when reading road signs in a different measurement system.
100 km × 4.9709695379 = 497.0969537899 fur
Kilometer to Furlong conversion table
Standard reference values for converting kilometers to furlongs:
| Kilometer [km] | Furlong [fur] |
|---|---|
| 0.01 | 0.0497096954 |
| 0.1 | 0.4970969538 |
| 1 | 4.9709695379 |
| 2 | 9.9419390758 |
| 3 | 14.9129086137 |
| 4 | 19.8838781516 |
| 5 | 24.8548476895 |
| 10 | 49.709695379 |
| 20 | 99.419390758 |
| 30 | 149.129086137 |
| 40 | 198.8387815159 |
| 50 | 248.5484768949 |
| 100 | 497.0969537899 |
| 500 | 2485.4847689493 |
| 1000 | 4970.9695378987 |
Frequently asked questions
How many furlongs is 1 kilometer?
How do I convert kilometers to furlongs?
How do I convert furlongs back to kilometers?
How many furlongs is 100 kilometers?
Popular length unit conversions
Convert Kilometer to other length units
Show all Kilometer conversions
Metric / SI (17 units)
Imperial / US Customary (27 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 km = 4.9709695379 fur) 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 Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.