How to Calculate the Slope of a DEM in QGIS in 3 Easy Steps:

1. Open the DEM in QGIS
2. Fill Sinks
3. Run The Slope Tool

Step 1

Open the DEM in QGIS

In this example, we use a DEM exported from the Equator Data Menu . To learn how to download a DEM, check out this tutorial:

How to Export USGS LiDAR as a DEM

Do you need a DEM? You can download it for free from Equator:

Open your DEM shapefile in QGIS by dragging and dropping the file into the map space.

Image of our DEM in QGIS

Step 2

Fill Sinks

Note: DEMs from Equator automatically fill sinks when exported.

If you did not get your DEM from Equator, follow the instructions below:

Using the fill sinks tool to generated a Filled DEM layer

Step 3

Run The Slope Tool

Now that we have projected our DEM onto our project, we will run the Slope tool:

Processing → Toolbox → Taster Terrain analysis → Slope

Set the input layer as your DEM, and adjust the other input settings as you deem appropriate (in this case we elected to leave the default settings):

Using the Slope tool to generate the final layer

Done!

You now have a layer with the slope of your DEM calculated in degrees!

We hope this helped, and feel free to take a look at some of Equator’s other blogs and “How-to tutorials” !