Differences Between ‘I Don’t Know’ and ‘I Don’t Understand’ in Japanese

Two words that are commonly confused by beginner/ intermediate students are 分かる and 知る. Gaijinpot has a look at the differences between these similar verbs.

By 3 min read

One of the biggest challenges that English-speaking learners face when they study Japanese are the two verbs ()かる (wakaru, to understand) and ()る (shiru, to know). This is because they are often translated into English as the same verb.

Speaking and listening to Japanese, you might also hear wakarimasen (I don’t understand) and shirimasen (I don’t know). Simply put, wakarimasen is used when you don’t understand something or what someone has asked and shirimasen is used when you don’t have the information.

However, within that slight difference in nuance lurks a lot of traps for the unwary.

Speaker and listener

Just nod and smile…

One of the most common uses of 分かる is to describe things known or understood to the speaker but not necessarily to the listener. For example:

Japanese English Romaji
明日何(あしたなに)をするか()からない. I don’t know what I will be doing tomorrow. Ashita nani o suru ka wakaranai.

This phrase is acceptable in Japanese because we probably know what we’re doing tomorrow. However, if you were to translate this—literally—into English using “understand,” it would be strange. After all, how can I not “understand” what I will do tomorrow?

They know, but I dont

Learners will also see a similar use of this meaning of 分かる in newspapers. In some articles, 分かる is used to infer that the words came from someone else. In this case, 分かる is used to imply that it is something that the person speaking had knowledge of. On the other hand, 知る implies that something is general knowledge, known to many people or is known by someone else. If we are talking about my wife, I might say:

Japanese English Romaji
わたしつま()(なに)をしているか()らない I don’t know what my wife is doing. Watashi ha tsuma ga nani wo shiteiru ka shiranai

Here, my wife understands what she is doing even if I do not.

Another example:

Japanese English Romaji
(にい)さんについて()らないことが(おお)すぎた There are a lot of things I don’t know about my big brother. Nisan ni tsuite shiranai koto ga oosugi ta

In this phrase, my brother knows what he is doing, but I have no clue.

Knowing before understanding

I don’t need to understand lyrics to ROCK!

Another use of the same vocabulary is to put things in order. In most situations 知る happens before 分かる, so looking at which noun is attached to 知る can help you understand how something happened. For example:

Japanese English Romaji
(うた)()っているけれど(じつ)意味(いみ)がよく()からない I know this song, but I don’t understand what it means. Uta wa shitteiru keredo jitsuwa imi ga yoku wakaranai

Learners should notice that the use of 知ってる (I know) here is very different from its equivalent in other languages. In English, translating 歌は知っている literally to “I am not understanding the song” would be very unusual.

Functional differences

Fluffy, shiranai yo!

Finally, there are also functional differences. For example, if your cat tries to jump off the roof, you might yell, “shiranai yo!” A literal translation would be “I don’t know.” But, in this context, shiranai sounds angry. It’s functioning as “you’re going to hurt yourself, but I don’t care.” Except, you actually do care.

Likewise, “wakaru” has a similar function in certain situations as saying wakatteiru (I know) often sounds dismissive of the listener’s opinion. For example, you just reminded your friend that you’re running late for the third time, and they snap, “wakatteiru!” at you. This is a bit like saying “I know! Stop telling me!” in English.

Ultimately, the best way to learn the differences is to keep speaking Japanese. Hopefully, as both are some of the most commonly used verbs, you can quickly grasp the situations where one or the other is used.

Think you understand and know the differences between wakarimasen and shirimasen now? Great! Do you know any more difficult Japanese differences? Let us know in the comments!

  • Nicholas Sturtevant says:

    Just one flaw with the image here. I’ll bet large sums of money that anyone who can use って in discourse will also know what 花見 is.

  • Sakamotoさん says:




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