 Hello, in this video we are going to derive the Strahler orders from the Flow Direction map. In the Processing Toolbox go to the PC Raster Tools and search for the Stream Order Tool. Choose the Flow Direction in the LDD format as an input and save the result as Strahler. Click Run and it will classify all the pixels to a Strahler order. Use the Layer Styling Panel to style the result. Strahler order rasters are an ordinal data type, which means that we have to use the pelleted unique values renderer, but we can use a ramp because there is a certain order in the classes. If we use a blue ramp, we can see that the bigger streams have a darker blue color. So in this video you have learned how to calculate the Strahler orders from the Flow Direction Raster.