When to use which kanji?


About 4 months in learning Japanese and almost done with Genki I and I’m finding there are some words in Japanese that can take several different kanji with the same pronunciation and meaning. Examples: 上る/登る、降りる/下りる. My question is, are there any rules to determine which kanji to use when? Are there subtle differences in the meaning of the word if you use a different kanji or are they just personal preferences?

I understand this exists because the native Japanese words were already in use when the kanji were imported from China and then subsequently associated with those words. But after having spent so many years learning Chinese where, for the most part, one character has one fixed reading, this is a bit confusing for me.

My biggest challenge now is remembering that Chinese and Japanese are two distinct languages and throwing all the rules I learned before out the window. There are still many times when I read a word in Japanese and immediately think of the Chinese pronunciation, especially if it’s a Chinese word (ex. 結婚する = jiehun suru), then it takes a second for my mind to put it into Japanese before it comes out of my mouth. :cry: :cry: :cry:


Take this with a grain of salt - I have been exposed to Japanese quite frequently and potently over the past few years, but I’m still entirely a beginner in the language. Also, forgive the lack of Japanese; my IME didn’t install properly on WIN10.

The Japanese language is full of homophones, as you know well already. This means that you end up with a range of words that sound the same but have different meanings - but what about words that sound the same and have the same meaning?

In this case, I would say that they actually don’t have the same meaning. There is a nuance that you’re missing. The easiest way to explain this is with an example:

暑 = heat, Pronunciation = atsui
熱 = heat, Pronunciation = atsui

They sound the same, and they mean the same thing. The difference, however, is in the nuance. The latter can only be used to refer to a fever (or a hot object/person), whereas the former refers to the weather.

There are also a number of words that mean ‘hard’ in very slightly different nuances and they have similar but not identical kanji.

I very much doubt there is an exact synonym for any word in any language; even if the meanings are the same, the usage of the word says something about you.

E.G. ‘trivial’ and ‘easy’ can be used as precise synonyms in this sentence:

“That exam was [trivial]!”
“That exam was [easy]!”

They mean the same thing, yet the nuance is different. The former has the effect of establishing you as either a pompous or articulate person, while the latter is everyday speech.

The same applies in Japanese, I would think.

Again, take this with a grain of salt. I’m just a beginner. This is just what seems to makes sense to me - I’m mostly guessing here. Perhaps post some examples of words that have confused you, and look up the kanji on jisho.org or another such website. That would be [instrumental] in helping us help you.
*ahem* You did give some examples; I just skimmed over it. Nevermind!



Thanks for your reply! I figured there were certain subtle nuances that had to be accounted for and what you said does make a lot of sense. I guess it’s all part of “doing” Japanese more and more and getting the feel for it through constant usage. I did find a Japanese-language site that explains the differences between a lot of these kinds of words:

I can make out the gist of what it says, but if my level of Japanese was higher it seems this would be a great resource. From what I can gather it’s saying 下りる is used in situation like “coming down the stairs” or the “the curtain is lowering”, while 降りる is used when getting off/out of vehicles.

On that note, does anyone know of any resources in English that list these types of words together and explain their subtle differences?


Shameless self promotion I guess, but @mamimumason made a great list with explanations of homophones like these:


Ah, I have this issue quite often with WaniKani and usually text my mom with like 3 synonyms asking when to use which one. There’s usually subtle nuances between the words. (For example I just texted my mom about 上る・登る today (登る is more of a voluntary climb whereas 上る is more like “to rise” so an elevator would use 上る and you would use 登る to climb a mountain)).

Anywayyy if my mom is unavailable or I’m feeling more studious I just google the word and try to find some context or use a japanese to english dictionary. Since wanikani trades more info for shorter simpler answers, a lot of nuance gets lost imo. (Good for the way wanikani is set up, not necessarily good for when I’m trying to create sentences lol)


Been wondering this myself, thanks for asking. I hoped I’d eventually figure it out through context but I should probably be more proactice in my studies :V


Thanks @Kristen, that article is fantastic!