must do; unless/if you don't~ (ないと) – Japanese Grammar ないと (naito)

Q: What JLPT level is ないと?

JLPT N3 — Intermediate · Expressing nuance & contrast

Q: How do you use ないと in a sentence?

Attach ないと to the appropriate verb or noun form. Must do; unless/if you don't~

Q: Is ないと formal or casual Japanese?

ないと can be used in both casual conversation and polite speech depending on context.

ないと

N3 GRAMMAR ⏱ 0s study 📖 0 today

naito

must do; unless/if you don't~

にかけて ni kakete かける kakeru さらに sara ni というのは to iu nowa ことは～が koto wa~ga は～で有名 wa~de yuumei ばかりで bakari de つもりで tsumori de 一体 ittai とおりに toori ni てしょうがない te shou ga nai 上に ue ni んだって ndatte すなわち sunawachi てもしょうがない temo shou ga nai のでしょうか no deshou ka に関する ni kan suru ても始まらない temo hajimaranai たとえ～ても tatoe~temo 最中に saichuu ni にかけて ni kakete かける kakeru さらに sara ni というのは to iu nowa ことは～が koto wa~ga は～で有名 wa~de yuumei ばかりで bakari de つもりで tsumori de 一体 ittai とおりに toori ni てしょうがない te shou ga nai 上に ue ni んだって ndatte すなわち sunawachi てもしょうがない temo shou ga nai のでしょうか no deshou ka に関する ni kan suru ても始まらない temo hajimaranai たとえ～ても tatoe~temo 最中に saichuu ni

🃏 Flashcard

ないと

naito

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must do; unless/if you don't~

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📊 Pattern Stats

JLPT Level N3

Intermediate · Expressing nuance & contrast

Reading naito

Post ID 50878

Patterns today 0

0 / 10 daily goal

📝 Usage Notes

must do; unless/if you don't~

📖 How to use it

Expresses obligation ('must do') or a conditional warning ('if you don't, then...').

Attaches to Attach to the ない-stem of a verb (the form before ない) plus と. For example, 行く -> 行かないと, 食べる -> 食べないと.

When used alone at the end of a sentence, ないと is a casual way of saying 'must' or 'have to'. It is a shortened form of ないといけない or なければならない. For example, '行かないと' means 'I have to go' or 'I must go'. It's common in everyday conversation, especially when reminding yourself or others of something necessary.

When followed by a consequence, ないと means 'if you don't do ~, then (a negative result)'. For instance, '勉強しないと、試験に落ちるよ' means 'If you don't study, you'll fail the exam.' In this usage, the second part often states an undesirable outcome or a warning.

Note that ないと is informal. In polite speech, you might use ないといけません or ないとだめです, but in casual conversation with friends or family, ないと is perfectly natural.

もう行かないと。

Mou ikanai to.

I have to go now.

宿題をしないと、先生に怒られるよ。

Shukudai o shinai to, sensei ni okorareru yo.

If you don't do your homework, the teacher will get angry.

明日テストがあるから、勉強しないと。

Ashita tesuto ga aru kara, benkyou shinai to.

I have a test tomorrow, so I have to study.

Not なければ (nakereba) なければ is more formal and means 'if not' or 'unless', and is often used with ならない. ないと is more casual and can stand alone to mean obligation. In a conditional sentence, なければ also expresses 'if not', but ないと often implies a stronger necessity or consequence.

🎯 Quick Quiz

What does this grammar pattern mean or do?

ないと

📚 How to Master This Pattern

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Say It Aloud

Press Hear it and repeat ないと three times. Feel the rhythm — grammar patterns have a natural flow.

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Flip Before Reading

Always try to recall the usage before flipping the card. Struggle = learning. Every failed recall makes the next one stick harder.

✍️

Write Two Sentences

Compose two original sentences using ないと. One about yourself, one about something you see right now.

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Spaced Review

Save this pattern and revisit at 10 min, 1 day, 3 days. Production (writing) beats recognition for grammar.

🔗 More JLPT N3 Patterns

← Previous

ないことはない

can do~; is not impossible to~

なかなか

quite~; pretty~; rather~; just not ~

❓ Frequently Asked Questions

What does the grammar pattern ないと mean? ▼

Must do; unless/if you don't~

What JLPT level is ないと? ▼

Nihoner currently groups this pattern under JLPT N3 — Intermediate · Expressing nuance & contrast. Use the level label as study guidance rather than a prediction of what will appear on an exam.

How do you use ないと in a sentence? ▼

Attach ないと (naito) to the appropriate verb or noun form as described in the usage notes. Then try writing two original sentences — one about yourself and one about something around you.

Is ないと formal or casual Japanese? ▼

ないと is used in both casual and polite contexts. It appears frequently in everyday conversation, textbooks, and simple written materials.

How can I remember ないと long-term? ▼

Use the flashcard on this page for active recall — see the pattern, reconstruct the usage from memory, then flip. Follow with the 4-choice quiz to distinguish it from similar patterns. Review later the same day and again over the following days. Writing original sentences can help you practise using the pattern in context.