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for zoom level N, the scale is one half of that of zoom level N-1.for zoom level 1, the scale is one half of that of zoom level 0.so the point is that the scale depends on your monitor's PPI and on the latitude (because of the Mercator projection).You cannot observe this in Google Maps since it automatically moves to the zoom level 1, but you can see it on OpenStreetMap's map (it uses the same tiling scheme).ģ60 degress on the Equator are equal to Earth's circumference, 40,075.16 km, which is 40075160 mĭivide 40075160 m with 0.065 m and you'll get 616313361, which is a scale of zoom level 0 on the Equator for a computer monitor with 100 DPI ![]() On zoom level 0, the whole 360 degrees of longitude are visible in a single tile. That means 256 pixels are roughly 6.5 cm of length. Let's say your computer monitor has 100 pixels per inch (PPI). Google's web map tile has 256 pixels of width.To help you understand the maths (not a precise calculation, it's just for illustration):
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