Pixels (CSS) to Nautical Miles (px to nmi)
1 pixel (CSS) equals 1.428635709×10⁻⁷ nautical miles (rounded).
How to convert pixels (CSS) to nautical miles
To convert pixels (CSS) to nautical miles, multiply the number of pixels (CSS) by 1.428635709×10⁻⁷. The factor is rounded to 10 significant digits. To go the other way, multiply nautical miles by 6,999,685.039 (rounded).
nautical miles = pixels (CSS) × 1.428635709×10⁻⁷
Example: 10 pixels (CSS) = 0.000001428635709 nautical miles.
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
Nautical Mile (nmi)
Exactly 1,852 meters, close to one minute of latitude. The standard unit of distance at sea and in aviation; one nautical mile per hour is one knot.
Sailors wanted a distance that matched their charts, so the nautical mile was tied to the globe itself: one minute of arc, one sixtieth of a degree, of latitude. Earth's polar circumference is therefore close to 21,600 nautical miles. Because Earth is flattened at the poles, a minute of latitude is about 1,843 meters at the equator and about 1,862 at the poles, so the fixed value of 1,852 meters is a compromise. France's definition of the meter produced a figure near 1,851.85 meters, which helped set the number.
The First International Extraordinary Hydrographic Conference in Monaco defined the international nautical mile as exactly 1,852 meters in 1929. The United States kept its own variant until 1954, and the United Kingdom adopted the international value in 1970. A speed of one nautical mile per hour is one knot. The unit is not part of SI but remains the norm in air, marine and space navigation and in defining territorial waters, because distances on a chart can be read straight off the latitude scale. Its symbols vary: NM, nmi and M all appear.
1 nautical mile = 1,852 meters (exactly).
Sources: Wikipedia: Nautical mile; NIST Guide to the SI, Appendix B.8: conversion factors
Related conversions
- Nautical miles to pixels (CSS) (reverse)
- Pixels (CSS) to meters
- Pixels (CSS) to kilometers
- 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 light-years
- Meters to nautical miles
- Kilometers to nautical miles
- Centimeters to nautical miles
- Millimeters to nautical miles
- Inches to nautical miles
- Feet to nautical miles
- Yards to nautical miles
- Miles to nautical miles
- Micrometers to nautical miles
- Nanometers to nautical miles
- Light-years to nautical miles
See all length units.