〜なくてもいい (nakute mo ii)

JLPT N4

How to say something isn't necessary — you don't have to do it.

Meaning

“You don't have to ~ / it's okay not to ~.” Relieves an obligation.

Formation

• Verb (ない-form, drop い) + くてもいい

• い-adj → くなくてもいい; Noun / な-adj → でなくてもいい

Examples

明日は来なくてもいいです。

Ashita wa konakute mo ii desu. — You don't have to come tomorrow.

全部食べなくてもいいよ。

Zenbu tabenakute mo ii yo. — You don't have to eat it all. (casual)

急がなくてもいいですよ。

Isoganakute mo ii desu yo. — You don't need to hurry.

予約しなくてもいい。

Yoyaku shinakute mo ii. — You don't have to make a reservation.

How it works

It's the negative of 〜てもいい (permission). Where 〜なければならない says “you must,” this says “you're free not to.”

Compared with similar expressions

• 〜なくてもいい — don't have to (no obligation).

• 〜なければならない — must (the opposite).

• 〜てもいい — may (permission to do).

Common mistakes

• From the ない-form, drop い, add くてもいい: 行かない → 行かなくてもいい

• Irregular: する → しなくてもいい

Related grammar

• 〜なければならない — must

• 〜てもいい — may

• 〜てはいけない — must not