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I found out that it is possible to get the elevation values for particular location, by using Google maps API:

https://developers.google.com/maps/pricing-and-plans/#details

What I couldn't find is the resolution of these elevation grid values?

Does Google maps use 3 arc-second (90 meters) for any other location outside of USA?

marco
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According to the API Docs, a request will send back JSON with a "resolution" value.

This corresponds to the distance between the points from which this value was interpolated. According to the docs, querying multiple points in one go can reduce the resolution.

I suspect this will vary according the part of the world you're interested in. Best way to find out is to send a few queries for a single point and see what values you get for resolution...

Steven Kay
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  • Thank you for the reply! I actually already tried sending a query, and got the resolution up to 4 meters (grid size) for Rome, Italy. However what makes me confused is whether or not his resolution is real, as 4 meters resolution may be raster data precision obtained through LIDAR sources. I have been googling and it looks like Google Earth has been using SRTM 1 arc-second (30 meters) resolution for locations in USA, and 3 arc-second (90 meters) resolution for locations outside of USA. I am wondering if Google maps actually uses this same SRTM raster data? – marco Aug 21 '16 at 23:00
  • do yo happen to know where can I find the information on the precision of the raster data that Google maps provides? I am actually in doubt that their resolution is an actual precision of their rasters. It is impossible to have such a high precision (4 meters for example) on the global scale. I would be grateful for any kind of reply. – marco Aug 23 '16 at 08:43
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    check out this answer for some speculation/observations. Link on that answer broken, sadly, but it hints that lidar derived data may be used in patches. – Steven Kay Aug 23 '16 at 19:31