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I have read all the buffer issues topics but haven't found solution to my problem.

I have two layers:

  1. Border layer of Tokyo ward - WGS 84 / Pseudo-Mercator 3857
  2. A CSV text layer with x,y coordinates of buildings which I saved in the same CRS.

Now, I need to buffer one (central) point from the point layer on the scale of the whole Tokyo to make some calculations. But when I add buffer and set the distance (cca 14 km) buffer actually has the distance of cca 11km.

enter image description here

I tried re-saving and opening the point layer, re-doing the layer couple of time. Followed all the instructions on other similar questions. But the same problem occurs. I have done the same on couple of cities more and there was no problem in making the buffer correctly.

Any other inputs?

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  • 8
    Web Mercator is absolutely wrong on distance calculations, and shouldn't ever be trusted for them, especially in high latitudes.
    – Vince
    Aug 10, 2019 at 20:14
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    The ArcGIS Help has a nice topic about this issue and the difference between a geodesic and euclidian buffer, see this: pro.arcgis.com/en/pro-app/tool-reference/analysis/…
    – Marco_B
    Aug 10, 2019 at 20:30
  • Thank you guys, all the other layer came in the right projection so I could make correct buffers and I assumed this one will work here.
    – Julija M
    Aug 10, 2019 at 20:56

1 Answer 1

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As @Vince already stated in comments, Web Mercator is not suitable for this.

Reproject your layers (Save as...) to a local metric one. Regarding epsg.io this could be UTM Zone 54N (EPSG:3095) for example.

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    Not to criticize - just an information - EPSG 3095 was defined for old Tokyo datum (on Bessel ellipsoid) and replaced by current EPSG 3100 (on JGD2000 - ITRF94).
    – Kazuhito
    Aug 11, 2019 at 0:53

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