Yes, cast iron frying pans are suitable for induction cooktops as well as all other common types of cooktops. Before first use, they must be seasoned to remove manufacturing residues and develop a natural non-stick layer (patina). To do this, first clean the pan with hot water, dry it thoroughly, and then heat it with a high-heat oil (e.g., sunflower oil) on the stovetop, in the oven, or on the grill until the oil smokes.