Der Plan ist in Ordnung.

to be

Breakdown of Der Plan ist in Ordnung.

• der Plan: the plan
• in Ordnung: fine

Questions & Answers about Der Plan ist in Ordnung.

Why is it Der Plan and not Den/Dem Plan?

Because Plan is the subject of the sentence, so it takes the nominative case. Der is the nominative masculine article. You’d use den Plan (accusative) as a direct object (e.g., Ich mag den Plan) and dem Plan (dative) after certain prepositions/verbs (e.g., Mit dem Plan bin ich einverstanden).

What is in Ordnung grammatically?

It’s a fixed prepositional phrase used predicatively with the copula sein. In other words, it functions as the predicate complement, meaning “OK / all right / acceptable.”

Why not just say Der Plan ist Ordnung without in?

That’s ungrammatical in modern usage. The idiomatic expression is in Ordnung. Without in, you’d be saying “The plan is order,” which doesn’t work here.

Does in Ordnung need an article, like in der Ordnung?

No. In this idiom you don’t use an article. In der Ordnung would literally mean “in the order (system/arrangement),” which is a different, non-idiomatic meaning.

Is Der Plan ist ordentlich a good alternative?