Converting a raster's letter value to a numeric value

I’m using a global hydrological group raster that Invest recommends. This raster assigns values using the letters A-D and in order for the model to run the raster needs to have a linear numeric value. Therefore I need to change the values from A-D to 1-4. I don’t know how to make this change within QGIS and I was hoping someone here could help me.

Welcome to the community forum @bbgardie!

Have you tried “Reclassify by Table” in QGIS?

~ Stacie