What is ROI?
ROI (return on investment) is the profit an investment brings relative to its cost.
Unlike ROAS, ROI uses profit. It tells you whether ads really earned money after product costs.
A campaign can have a high ROAS and negative ROI when margins are thin.
Formula
ROI = (gross profit - ad spend) / ad spend x 100
Example
Ads cost 1,000 EUR and brought 1,500 EUR gross profit. ROI is 50 %.