Method for determining the cuttability of a compact graphite iron, characterised by the steps of: - arriving at a relationship between cuttability and contents of carbide-stabilising substances in compact graphite iron, which relationship is arrived at empirically from measured cuttability and measured contents of carbide-stabilising substances in a plurality of test pieces of compact graphite iron; - providing a compact graphite iron; - determining the contents of carbide-stabilising substances in the compact graphite iron provided; - determining a value for the cuttability of the compact graphite iron provided on the basis of the relationship and contents of carbide-stabilising substances in the compact graphite iron provided.