Posted on January 19, 2023 (Updated on July 10, 2025)

Calculating the percentage of polygons overlapping within the same layer in QGIS

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How does Qgis calculate overlap?

Duplicate the same layer and select the spatial query tool. Add the original and the copied layers. Select overlap instead of intersection. Run it, and you find the intersecting buffers highlighted.
 

What is percentage overlap?

This powerful feature allows the time axis on the Spectrogram and 3-D Surface plot to be “stretched” by re-processing portions of the time series. The setting determines what percentage of the FFT size block of data points is re-used for the next trace.

How does Qgis calculate percentage?

Quote from video: Call it percentage. It's also a decimal. Number open a bracket go to fields and values double click on the class area. And divide it by the catchment. Area close to brackets.

How do I remove overlapping polygons in Qgis?

You can use the ‘Check Geometries’ plugin (Vector/Geometry Tools/Check Geometries) to remove overlapping areas. Save this answer.
 

What is the formula for calculating overlap?

Overlap = min(A2, B2) – max(A1, B1) + 1. In other words, the overlap of two integer intervals is a difference between the minimum value of the two upper boundaries and the maximum value of the two lower boundaries, plus 1.
 

How do you do overlap analysis?

Quote from video:

How does QGIS calculate Lat Long?

formulas from above links: longitude= x(transform($geometry, ‘EPSG:FROM’, ‘EPSG:4326’)) and latitude = y(transform($geometry, ‘EPSG:FROM’, ‘EPSG:4326’)) for WGS84 lat/long.

How does Arcgis determine overlapping polygons?

Finding polygon overlaps and gaps that are slivers

  1. Start ArcMap.
  2. On the main menu, click Customize > Toolbars > Data Reviewer.
  3. Click the Select Data Check drop-down arrow on the Data Reviewer toolbar, click the plus sign (+) next to Feature on Feature Checks, then click Polygon Overlap/Gap is Sliver Check.

How do you know if a polygon is overlapping?

That said, if by polygons overlapping you mean at least one point of one is inside the other, you can test each polygon’s point against the others by either looking at the point in point polygon problem or checking each polygons lines to see if it cuts across another polygon.