V-ない stem + なくてもいい
don't have to
The absence of obligation — the direct counterpart of なければならない. Don't confuse it with 〜てはいけない (must not). "You don't have to come" and "you must not come" are opposite messages built from similar parts.
明日は来なくてもいいです。
あしたは こなくても いいです。
You don't have to come tomorrow.
急がなくてもいいですよ。
いそがなくても いいですよ。
There's no need to hurry.