WhiteboxTools functionality can also be accessed conveniently through the popular open-source geospatial software QGIS. QGIS developer Alexander Bruy maintains a plugin for the toolbox called WhiteboxTools For Processing.
The Whitebox for QGIS plugin works QGIS v3 but cannot be installed on the earlier v2 series. The minimum QGIS version supported by the plugins is currently 3.18.0. If you are using an older version of QGIS, you will need to update before the following procedure for installation will work.
Please note, as of February 2022, Alex Bruy is no longer distributing any of his numerous QGIS plugins, in protest of the war in Ukraine. We are currently working on developing a new WhiteboxTools frontend for QGIS in-house at Whitebox Geospatial Inc. Until this new frontend is release, we recommend downloading the existing plugin from here and installing the downloaded file using the Plugins Install From ZIP option in QGIS.
Once you have installed the ZIP file plugin, select Options from under the Settings menu in QGIS. Select the Processing tab and the Providers list item. You should find the WhiteboxTools entry there. Enter full file name of the WhiteboxTools executable file contained within the decompressed WhiteboxTools folder that you downloaded previously (Note: The QGIS plugin does not come with WBT installed; you will need to visit the Whitebox Geospatial webpage, and download and decompress WhiteboxTools from there prior to installing the QGIS plugin). If you double-click the white space beside the 'WhiteboxTools executable' label, the space should become editable and a '...' file selection button should appear to allow you to navigate to your executable file. If you are using a Mac or Linux computer, note that this may require you to 1) select a file contained in the folder that is not the executable (QGIS seems to exclude files without extensions, which the WhiteboxTools executable is on MacOS and Linux) then delete the file extension (see below). You may also manually enter the file path and name in the textbox if file selection does not work. You will also need to leave the textbox by selecting any other feature on the dialog box before pressing the OK button.
Because the QGIS WhiteboxTools frontend is maintained solely by the generosity of volunteers (namely Alex Bruy), it is sometimes the case that it is not up-to-date with respect to the number and parameterization of tools in the latest version of the WhiteboxTools backend, or the WhiteboxTools extension products. Nevertheless, there is a process by which you can manually update the tool descriptions to be in sync with the latest version of WhiteboxTools. See here for instructions on how to update the QGIS frontend to include all of the tools that are available in the most current version of the WhiteboxTools backend, including any tools that are part of a WhiteboxTools extension product.