Available Scale Levels
Scale level 0 is the most scalable zoom level, and each integer step in the zoom level reduces the X and Y extents of the view and doubles the linear resolution.
Google maps were built on a system with 256x256 pixel tiles, where the zoom level 0 was a 256x256 pixel image of the whole earth. The 256x256 tile for zoom level 1 enlarges the 128x128 pixel area from zoom level 0.
As bkaid correctly pointed out, the available zoom range depends on where you are looking and the type of map you are using:
- Roadmaps appear to be approaching level 22 everywhere.
- Hybrid and Satellite Maps — The maximum zoom level varies by location. Here are some examples:
- Remote Antarctica: 13
- Gobi Desert: 17
- Most of the USA and Europe: 21
- Deep Zoom: 22-23 (see bkaid link )
Note that these values apply to the Google Static Maps API , which seems to provide another level of scaling than the Javascript API. It seems that the extra zoom level available for static maps is just an extended version of the maximum resolution image from the Javascript API.
Map scale at various zoom levels
Google Maps uses the Mercator projection, so the scale changes significantly with latitude. The formula for calculating the correct scale based on latitude is:
meters_per_pixel = 156543.03392 * Math.cos(latLng.lat() * Math.PI / 180) / Math.pow(2, zoom)
Formula from Chris Broadfoot Comment .
JeremyD Sep 04 '15 at 21:51 2015-09-04 21:51
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