“C’est simple comme bonjour” is one of my favorite French expressions. The literal trasnlation is: “it’s as easy as hello” and meanings include “it’eas easy as pie”, “it’s easy as ABC” and “it’s as simple as that”. A French-to-French translation is “c’est vraiment très facile” (it’s really very easy).
simple comme bonjour
easy as pie

According to Expressio.fr, other meanings include “dead simple”, “easy to do”, “easy to understand” and “obvious”. Linternaute.fr suggests that the expression dates to the 19th century when the idea of greeting somebody with “bonjour” (hello) was associated with great simplicity.
Here are some example sentences:
Écoute, la recette est vraiment facile à préparer. Tu mélanges tous les ingredients dans un bol et c’est tout. C’est simple comme bonjour !
Listen, the recipe is really easy to prepare. You mix all the ingredients in a bowl and that’s it. It’s as simple as that!
Il ne faut pas suranalyser la situation. C’est simple comme bonjour !
There’s no need to overthing the situation. It’s dead simple.
Here are some synonymous expresssions in French
- C’est du gâteau – Literally: it’s cake
- C’est facile comme tout – Literally: easy as anything
- C’est bête comme chou – Literally: stupid like cabbage
Conclusion
Congratulations! You you know how to use the French expression simple comme bonjour. Now check out some other fun French expressions such as avoir le cafard (to be depressed) tomber dans les pommes (to faint), être dans la lune (to have your head in the clouds).