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I have a point layer in QGIS in EPSG:4326 and want to create polygon-circles of 10m radius around each point. All of the points are located within a squarekilometer in northern Germany. How do I do this? Buffering generates circles which are ellipses and way too big.

I'm quite unexperienced with GIS and I honestly searched the old questions before I posted this.

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    Please define what you mean by "buffering doesn't seem to work". Which CRS is your point layer in? – Erik Oct 2 at 10:01
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    Following on from @Erik, when you try to buffer does it result in polygons that are way too big or does it fail to even run? If it fails then what error does it throw? The CRS (Coordinate Reference System) of your data needs to be in metres if you want to buffer it by x metres, data can usually be reprojected easily so if it isn't in the correct CRS then it's fixable. – TeddyTedTed Oct 2 at 10:16
  • Thank you for answering! The CRS is EPSG:4326 (if that makes any sense), and when I buffer the "circles" are neither circle shaped nor the right size (way too big). That might be because the CRS is not in meters... – Chris Oct 2 at 10:31
  • Check this thread gis.stackexchange.com/questions/37219/…, you will an appropriate CRS for Germany there, either Gauss-Krüger (zone 2, 3, 4 or 5) or UTM (zone 32 or 33). – Taras Oct 2 at 10:54
  • Also check this tool in QGIS "Rectangles, Ovals, Diamonds" – Taras Oct 2 at 11:00
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From your comment your data is in EPSG 4326 which is WGS 84, this uses latitude and longitude coordinates, so when you tell that to buffer by 10 it buffers by 10 degrees which is massive.

To get your point layer to use metres instead you will need to convert it to a CRS which uses metres. You will need to right click on the layer in the table of contents, then Export > Save Features As and as part of saving them choose an appropriate CRS. Choosing the right CRS depends on where in the world your data is. Google is your friend here to find out what's the right CRS.

This new dataset should now buffer correctly.

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    Good answer. Since the OP says all his points are within 1 sq km in Germany, any projected CRS that works well in Germany will work for them, and give essentially identical results for a 10m buffer. EPSG:5243 is one that they can use if no-one else is prescribing other guidance. – Houska Oct 2 at 10:51
  • Thanks @Houska, I'm not familiar with CRSs for Germany so I was hesitant to recomment any. TIL EPSG:5243 is the way to go. – TeddyTedTed Oct 2 at 11:00
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    Usually we're using 25832 (UTM 32N) and 25833 (33N). This is supported by next to all official sources. – Erik Oct 2 at 11:03
  • Thank you so much guys, it worked! – Chris Oct 2 at 11:30
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    Please mark it as the answer if it did the job. – MarcM Oct 2 at 12:18

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