N5April 26, 20266 min read

ないといけない: must do

Learn how to use ないといけない, a JLPT N5 Japanese grammar point meaning must do, with structure, nuance, examples, mistakes, and comparisons.

ないといけない means must do. It is a JLPT N5 Japanese grammar pattern used to express obligation or necessity.

This grammar point appears often in beginner conversations, classroom Japanese, and JLPT-style questions. If you want to say that an action is required, ないといけない is a useful pattern to learn because it helps you build natural basic sentences.

What does ないといけない mean?

Use ないといけない when you want to show that someone has an obligation to do something.

Natural translations include:

The exact English translation changes with context. Focus on the role of the grammar point in the sentence first, then choose the English phrase that sounds natural.

How to form ないといけない

Verb negative stem + ないといけない

Examples of the pattern:

Pay attention to the word form before and after the pattern. Many beginner mistakes happen because the meaning is understood, but the grammar is attached to the wrong form.

When is ないといけない used?

Use ないといけない in situations like:

Tone and register:

ないといけない example sentences

Read the Japanese sentence first, then check the English translation. Try to notice what the grammar point contributes: question, contrast, reason, time limit, suggestion, negation, or obligation.

Nuance of ないといけない

The key nuance is necessity based on a rule, situation, or responsibility.

This matters because beginner Japanese often uses small words and endings to show meaning that English expresses with word order or helper verbs. For ないといけない, the sentence can change a lot depending on placement and context.

For example:

ないといけない vs なければならない

Both ないといけない and なければならない can express related ideas, but they are different.

ないといけない:

なければならない:

Quick contrast examples:

If you are unsure which one to use, ask what the sentence is trying to do: ask a question, connect ideas, show a reason, mark time, make an invitation, or express obligation.

Common mistakes with ないといけない

Watch out for these mistakes:

A good study habit is to write one short sentence and then change only the grammar point. This makes the difference between similar patterns easier to feel.

Is ないといけない on the JLPT?

Yes. ないといけない is commonly taught as JLPT N5 grammar.

That means learners should be able to:

For test preparation, do not only memorize the English gloss. Practice identifying the words around the grammar point, because JLPT questions often test structure and context together.

Practice questions for ないといけない

Try making your own sentences with these prompts:

Keep the sentences short at first. Once the form feels natural, add time words, places, reasons, or contrast to make the sentence more realistic.

Learn ないといけない with Kanjiru

If you want to review ないといけない together with kanji, vocabulary, and other JLPT N5 patterns, Kanjiru helps you practice Japanese in short, focused sessions.

Browse more lessons here:

FAQ about ないといけない

What does ないといけない mean in Japanese?

ないといけない means “must do” in Japanese. It is an N5 grammar point, and this lesson explains its formation, nuance, example sentences, common mistakes, and similar grammar.

Is ないといけない on the JLPT?

ないといけない is taught as N5 Japanese grammar in Kanjiru's grammar lesson archive. Review it with examples, usage notes, and related N5 patterns.

How should I practice ないといけない?

Read several example sentences, identify the form before and after ないといけない, then make your own short sentences and compare it with nearby grammar points.

Practice grammar with Kanjiru

Use Kanjiru for short Japanese practice sessions across kanji, vocabulary, grammar, reading, and JLPT review.