On request of Rainforest Alliance, Agri-Logic developed a tool for its cocoa certification programme that allows certificate holders to quickly and reliably estimate the gap to the living income of farmers in its supply chain. The model in the tool was developed from a large set of Farmer Field Book time-series data from Ghana and Cote d’Ivoire. The model relies on the very strong relationship between a farmer’s production level and income. Tool users need only add data on 5 variables for each farmer to the tool. The 5 variables are in most instances already available in existing datasets of the certificate holder and as such require no additional data collection. Reliability testing showed the tool to be highly accurate, erring no more than a single percentage point when assigning farmers to above and below the living income categories. This tool is currently being rolled by Rainforest Alliance to cocoa certificate holders who wish to report on living income development.