Switzerland runs on 230 V at 50 Hz, with sockets following Types C and J. A converter can stay at home; Switzerland supplies 230 V.
Handy for multi-stop trips: Liechtenstein use the same plug types. Nearby but different: Gibraltar, Cyprus and Malta – an adapter for Switzerland will not fit there. In Europe, 2 of 50 recorded destinations use exactly this combination.
Protective earth
Grounded and ungrounded sockets may occur
Switzerland has sockets with a protective earth (Type J) and without (Type C). A plug that fits mechanically does not guarantee earthing.