A foot is exactly 0.3048 meters.
Feet to Kilometers Converter — ft to km
Convert Foot (ft) to Kilometer (km) using the exact conversion factor (1 foot = 0.0003048 kilometer). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Feet to Kilometers converter
Converter
Length Converter
Convert SI, imperial, US customary, astronomical, scientific, and historical length units.
Context values
Some unit families need one extra value for a physically accurate result.
Kilometer is 1000 meter units.
Result = input x 0.3048 / 1000.
Length uses the meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Feet to Kilometers
Foot and Kilometer both measure length. Foot is typically associated with united States (height, construction, aviation altitude), while Kilometer is typically associated with standard road, distance, and mapping unit in nearly every country except the United States.
Formula
kilometers = feet × 0.0003048
This factor comes from each unit's defined relationship to the category's base unit: 1 foot equals 0.3048 base units, and 1 kilometer equals 1000 base units, so dividing one by the other gives the direct foot-to-kilometer factor of 0.0003048.
Simple example
1 ft × 0.0003048 = 0.0003048 km
1 foot = 0.0003048 kilometers.
Real-world example
10 ft × 0.0003048 = 0.003048 km
10 feet = 0.003048 kilometers.
Conversion table
| Foot (ft) | Kilometer (km) |
|---|---|
| 1 ft | 0.0003048 km |
| 5 ft | 0.001524 km |
| 10 ft | 0.003048 km |
| 21.0975 ft | 0.006430518 km |
| 42.195 ft | 0.012861036 km |
| 100 ft | 0.03048 km |
Reverse conversion: Kilometer to Foot
0.0003048 km × 3280.839895 = 1 ft
0.0003048 kilometers = 1 feet.
feet = kilometers × 3280.83989501
For a page dedicated to this direction, see Kilometer to Foot.
Foot vs. Kilometer
| Aspect | Foot | Kilometer |
|---|---|---|
| Family | US/imperial customary unit | SI derived (metric prefix) unit |
| Typical use | Height measurement in the US and UK | Road signage, speed limits, and vehicle odometers outside the US |
| Where it's used | United States (height, construction, aviation altitude) | Standard road, distance, and mapping unit in nearly every country except the United States |
Understanding the Foot
Foot (ft) measures distance. The international foot is defined as exactly 0.3048 meters. It is classified as a US/imperial customary unit.
Where it's used: United States (height, construction, aviation altitude) United Kingdom (height, some construction contexts)
Uses of the Foot today
- Height measurement in the US and UK
- US construction and real estate (square footage)
- Aviation altitude worldwide (feet remain standard even in metric countries)
History of the Foot
The foot has ancient roots (Roman 'pes', various regional English feet), standardized into the modern English foot over centuries. The international foot (exactly 0.3048 m) was fixed by the 1959 International Yard and Pound Agreement, resolving small historical differences between US and UK measurements.
Historical origin. Foot was not the invention of a single named person; it developed through the process described above.
Understanding the Kilometer
Kilometer (km) measures distance. A kilometer is 1,000 meters — the meter is the SI base unit of length. It is classified as a SI derived (metric prefix) unit.
Where it's used: Standard road, distance, and mapping unit in nearly every country except the United States
Uses of the Kilometer today
- Road signage, speed limits, and vehicle odometers outside the US
- Geographic and mapping distances
- Endurance sports (marathons are measured in kilometers internationally, though the marathon distance itself is a fixed value in both systems)
History of the Kilometer
The meter was defined during the French Revolutionary metric reforms as one ten-millionth of the distance from the North Pole to the Equator along a meridian through Paris. 'Kilo-' is simply the SI prefix for 1,000, making the kilometer a direct decimal multiple.
The meter itself has been redefined several times as measurement precision improved — from a physical platinum-iridium bar (1889) to a krypton-86 wavelength (1960) to its current definition (1983) as the distance light travels in a fixed fraction of a second.
Historical origin. Kilometer was not the invention of a single named person; it developed through the process described above.
Foot — sources
- NIST — International yard and pound (1959) — Fixes the modern foot at exactly 0.3048 meters.
Kilometer — sources
- BIPM — The metre (SI base unit) — Current definition and history of the meter.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilometers are in 1 foot?
1 foot equals 0.0003048 kilometers, using the exact defined conversion factor rather than an estimate.
How do I convert foot to kilometer?
Multiply the foot value by 0.0003048. The converter above does this instantly to whatever precision you set.
How do I convert kilometer back to foot?
Use the reverse factor: 1 kilometer equals 3,280.839895 feet. You can also use the swap control in the converter above to flip the direction instantly.
What is a foot?
Foot (ft) measures distance. The international foot is defined as exactly 0.3048 meters. It is classified as a US/imperial customary unit.
What is a kilometer?
Kilometer (km) measures distance. A kilometer is 1,000 meters — the meter is the SI base unit of length. It is classified as a SI derived (metric prefix) unit.
Is the foot to kilometer conversion exact?
Yes. The international foot is defined as exactly 0.3048 meters. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
Where is the foot still used today?
United States (height, construction, aviation altitude) United Kingdom (height, some construction contexts)