Pixels (CSS) to Kilometers (px to km)
1 pixel (CSS) equals 2.645833333×10⁻⁷ kilometers (rounded).
How to convert pixels (CSS) to kilometers
To convert pixels (CSS) to kilometers, multiply the number of pixels (CSS) by 2.645833333×10⁻⁷. The factor is rounded to 10 significant digits. To go the other way, multiply kilometers by 3,779,527.559 (rounded).
kilometers = pixels (CSS) × 2.645833333×10⁻⁷
Example: 10 pixels (CSS) = 0.000002645833333 kilometers.
About these units
Pixel (CSS) (px)
The CSS reference pixel, defined as 1/96 of an inch. Physical screens vary, but browsers use this value to convert pixels to print units.
Pixel is a contraction of picture element, itself built from pix, a 1930s shortening of pictures. The idea is older than the word: Paul Nipkow's 1888 German patent spoke of a Bildpunkt, or picture point, and the phrase picture element appears in US patents filed as early as 1911. Frederic C. Billingsley of the Jet Propulsion Laboratory published pixel in 1965, writing about scanned images from space probes to the Moon and Mars, and said he had learned it from Keith E. McFarland, who reported it was already in use around 1963.
A pixel in a photograph is a sample, not a fixed length, and screens vary widely in size. CSS therefore defines px as an abstract reference pixel of exactly 1/96 inch, based on the visual angle of one pixel on a 96 dpi device held at arm's length. The CSS specification gives that angle as about 0.0213 degrees for a nominal arm's length of 28 inches, which works out to about 0.26 mm. On sharper screens a single CSS pixel spans several device pixels. Earlier CSS versions did not fix the ratio, but too much existing content assumed 96 dpi.
1 pixel (CSS) = 0.0002645833333 meters (approximately).
Sources: W3C: CSS Values and Units Module Level 3, absolute lengths; Wikipedia: Pixel
Kilometer (km)
1,000 meters. The standard unit for road distances in most countries.
A name for 1,000 meters took a while to settle. In 1793 France's National Convention made the metre the sole French unit of length, and the first proposed name for the thousand-metre multiple was millaire. Everyday French usage then leaned on the myriametre, 10,000 meters, well into the 1800s. The Netherlands adopted the kilometre in 1817, under the local name mijl, and made it the only official unit of that size in 1867. In 1935 the CIPM dropped the myria- prefix, which left the kilometre as the standard unit for road-scale distances.
Kilo- is the SI prefix for a thousand, and the kilometre is now the preferred unit for land distances in most of the world, with the United States, the United Kingdom and Liberia among those that still use the mile. One kilometre is about 0.621 mile. The main span of Lisbon's 25 de Abril Bridge, at 1.013 km, gives a sense of the scale. Even its pronunciation has been argued over: in 1970 Australia's Metric Conversion Board made stress on the first syllable official, although Prime Minister Gough Whitlam argued for stress on the second. Military slang in several countries calls it a klick.
1 kilometer = 1,000 meters (exactly).
Sources: Wikipedia: Kilometre; Wikipedia: Metric prefix; BIPM: history of the metre
Related conversions
- Kilometers to pixels (CSS) (reverse)
- Pixels (CSS) to meters
- Pixels (CSS) to centimeters
- Pixels (CSS) to millimeters
- Pixels (CSS) to inches
- Pixels (CSS) to feet
- Pixels (CSS) to yards
- Pixels (CSS) to miles
- Pixels (CSS) to micrometers
- Pixels (CSS) to nanometers
- Pixels (CSS) to nautical miles
- Pixels (CSS) to light-years
- Meters to kilometers
- Centimeters to kilometers
- Millimeters to kilometers
- Inches to kilometers
- Feet to kilometers
- Yards to kilometers
- Miles to kilometers
- Micrometers to kilometers
- Nanometers to kilometers
- Nautical miles to kilometers
- Light-years to kilometers
- Picometers to kilometers
See all length units.