This article measures the productivity index of the Old English suffixes -cund, -ful, and -isc as well as the prefix ful- and checks the results against the diachronic evolution of the affixes. The frameworks brought to the discussion include Type frequency measurement, as well as productivity indexes proposed by Baayen (1992, 1993, 2009) and Trips (2009). The sources are both textual (The Dictionary of Old English Corpus) and lexicographical (the lexical database of Old English Nerthus). The conclusion drawn is that Baayen's (1992, 1993, 2002) index of Global Productivity provides the most consistent results with the diachronic evolution of the affixes.