Plug Type in Denmark

In short Denmark uses Type C, E, F and K sockets, running at 230 V and 50 Hz. The Danish Type K socket has its earth as a pin below the two live holes, which gives it the smiling face that made it briefly famous. Danish sockets accept C, E and F as well, so in practice almost any European plug works. At 230 V, anything whose label reads 100–240 V is fine with a shape adapter alone — that covers essentially every phone charger, laptop supply and camera charger. Anything marked 120 V only needs a converter, which is a different and much heavier object. The distinction to hold on to is that a plug adapter and a voltage converter are different objects: the adapter changes the shape so the plug enters the socket and passes the local mains straight through, while the converter changes the voltage. Almost everything sold as a travel adapter is only the first, which is exactly why it cannot protect anything. Frequency — 50 Hz here — matters much less than people expect, because any device with a switch-mode power supply converts the incoming mains to DC immediately and ignores it. It affects mains-synchronous motors and old mechanical clocks, which run proportionally fast or slow, and very little else.