das Klo
toilet / loo
A colloquial word for the toilet or restroom.
Entschuldigung, ich muss mal schnell aufs Klo.
Excuse me, I need to quickly go to the toilet.

toilet / loo
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toilet / loo
A colloquial word for the toilet or restroom.
Entschuldigung, ich muss mal schnell aufs Klo.
Excuse me, I need to quickly go to the toilet.

'Klo' (toilet/loo) is the most common word for a toilet in everyday speech. It is used among friends and family, but in very formal or business situations, 'Toilette' (toilet) or 'WC' (restroom/WC) are often more appropriate.
Wo ist hier denn das Klo, bitte?
Where's the toilet here, please?
A very common and important phrase is 'aufs Klo gehen' (to go to the toilet) or 'aufs Klo müssen' (to need to go to the toilet). Note the preposition 'auf' with the accusative to express movement toward it.
Die Kinder müssen vor der langen Autofahrt noch mal aufs Klo.
The children need to go to the toilet once more before the long car ride.
'Klo' is a shortened form of the word 'Klosett' (closet/toilet). The word 'Klosett' itself was borrowed from English ('closet'), but today it is hardly used in German anymore.
Früher stand auf den Türen oft „Klosett“.
In the past, the doors often said 'Klosett'.
bathroom / bath
'das Bad' and 'das Klo' can both have to do with the toilet room in everyday language, but they are not the same. 'Das Bad' means the room used for personal hygiene, often with a sink, shower, or bathtub, and sometimes also a toilet. 'Das Klo' directly means the toilet or the toilet room and is colloquial. The words can be confused because in many apartments the toilet is in the bathroom. If you want to speak more politely or neutrally, you are more likely to say 'Toilette' or 'Bad', depending on the situation; 'Klo' sounds very everyday and informal.

Entschuldigung, wo ist hier das Klo?
Excuse me, where is the toilet?
Morgens putzt Moritz im Bad seine Zähne.
In the morning, Moritz brushes his teeth in the bathroom.