At least three primary iceberg calving styles have been identified in Greenland: serac collapse, which produces falling icebergs tens of meters in length; buoyant flexure, which produces capsizing icebergs hundreds of meters in length; and tabular rifting, which produces kilometer-scale icebergs. However, calving styles are mostly undocumented across Greenland. Here, we develop a method to disentangle the sizes of individual calving events and map the dominant calving style at glaciers, using the characteristic properties of step retreats in satellite-derived terminus positions. At glaciers known to frequently produce glacial earthquakes, step retreats greater than 200 meters account for >80% of net retreat since 2018. In contrast, at glaciers known to calve by serac failure, 200 meter step retreats account < 20% of net retreat. Thus, terminus change timeseries can offer promising insight into the dominant calving styles at marine-terminating glaciers.