What Does desu Mean in Japanese? Everyone Has to Learn it

I watched a video the other day that said that the top 1,000 Japanese words are used for 70% of conversations. But perhaps the most commonly used word in Japanese is the copula です (desu). What does desu mean in Japanese? And the the heck is a copula?

First off, here is the definition of the word copula:

Pretty simple, it’s a connecting word that is usually the word be.

Don’t worry, it’s not as weird as it sounds. But it is absolutely a word that you will have to learn and understand if you want to be able to achieve any level of understanding in the Japanese language.

Let’s get started!

desu – What Does it Mean and How Do You Use it?

Simply put, the Japanese word です (desu) means “to be” and is often used just like the English words “be, is, am, are” and so on.

This whole topic is Japanese 101 for beginners so I’ll assume that you’re new. Since です (desu) is a verb, it has to go at the end of a sentence. This is a lot different from English and might be one of the reasons English natives usually find learning Japanese hard at first.

Also, even though it is made from the two kana で (de) and す (su) to form です (desu), it actually sounds like “dess” when it is spoken. That final “u” sound is basically silent. It’s not always 100%, but like maybe 90% or so.

Also, the form will not change when you are using it to talk about yourself, someone else, or even multiple people. That aspect of the language makes it easy.

  • I’m Nick.
    (nikku desu)
  • Where is the post office?
    (yuubinkyoku wa doko desu ka)

But of course there is more to it than just that simple explanation. There are certain sentences/phrases where you wouldn’t use “is/are” in English, but you still need to use です (desu) in Japanese.

  • I like apples.
    (ringo ga suki desu)

This faucet of Japanese is a little tricky to explain, but you will pick up on it after practicing the language for a while.

To talk about things in the past, you simply change です (desu) to でした (deshita). And just like how the “u” in desu is hardly pronounced, the “i” in deshita is also silent. The word でした (deshita) sounds like “deshta” to the human ear.

  • This was a banana.
    (kore wa banana deshita)

The negative form of です (desu) totally changes form to ではありません (de wa arimasen).

  • That is not a table.
    (sore wa teeburu de wa arimasen)
  • These aren’t my shoes.
    (korera wa watashi no kutsu de wa arimasen)

And the past-negative is a combination of these last two forms into: ではありませんでした (de wa arimasen deshita).

  • It wasn’t a cat.
    (neko de wa arimasen deshita)

Just like all other Japanese verbs, です (desu) has both an informal form and a formal form. Or you could say that it has a casual form and a polite form if that makes it a little easier to understand.

What you just learned above was the polite (formal) form. This is the one that you’ll want to use when you meet new people and talk to them in Japanese. But if you watch Japanese anime, or read Japanese manga then you will most likely run into the casual (informal) form more often.

desu – Different Levels of Politeness

The informal form of です (desu) is だ (da). Generally speaking, the more polite a form is, the longer the verb will be. Therefore, these informal words will be shorter in length than what you’ve already learned.

  • Where is the dog?
    (inu wa doko da no)
  • It is a red bike.
    (akai jitensha da)

Although for a lot of situations, instead of changing です (desu) to だ (da) Japanese people will just drop the copula all together.

  • I’m sad.
  • Where is mom?
    (haha wa doko)

But you can’t drop it off when you use it in the past form or in the negative form. The past form of だ (da) is だった (datta).

  • What was the weather like?
    (tenki wa dou datta)

I’m sure you noticed in the last section when です (desu) changed to negative, it completely morphed into a new word. The same things happens in the casual/informal form. だ (da) changes to ではない (de wa nai).

Side note: では (de wa) can be contracted into じゃ (ja). じゃ (ja) is a little less formal than では (de wa) and じゃ (ja) tends to get used by Japanese people in daily conversations more often.

  • That is not a bird.
    (are wa tori de wa nai)
  • That is not a bird.
    (are wa tori ja nai)

And finally, past-negative is じゃなかった (ja nakatta) or ではなかった (de wa nakatta).

  • It wasn’t a good letter.
    (yoi tegami de wa nakatta)
  • It wasn’t a good letter.
    (yoi tegami ja nakatta)

Final Bonus Section!

This last part is really only used when you need to be super polite. So in business situations, or when talking to someone whom you want to show a great deal of respect towards.

です (desu) gets turned into でございます (de gozaimasu). What a mouthful! But I’m sure you recognize that ございます (gozaimasu) from words like “good morning” お早うございます (ohayou gozaimasu) and “congratulations” おめでとうございます (omedetou gozaimasu).

I wouldn’t worry about this ultra formal version too much as you probably won’t need to use it all that often. As a non-Japanese person, you tend to get a free pass when it comes to these things.

The past is でございました (de gozaimashita). The negative is ではございません (de wa gozaimasen). And negative-past is ではございませんでした (de wa gozaimasen deshita).

Wow, ten syllables just to politely say “was not” in Japanese, lol!

desu – How is it Differet from “iru” and “aru”

Are you familiar with the verbs いる (iru) and ある (aru) in Japanese? They both mean “there is / are” in Japanese, which is similar to how です (desu) is used, but are some differences for when you’d use one over the other.

Side note: いる (iru) is used for for people and animals, whereas ある (aru) is used for things.

One thing that is similar between all of these three verbs is that they can be used to tell the location of things and people.

  • Where is Tom?
    (tomu wa doko desu ka)
  • Where is Tom?
    (tomu wa doko ni iru no)

The words いる (iru) and ある (aru) both mean “to exist” and they usually mean “it exists for me” which gets translated as “I have” in English.

  • I have an apple.
    (ringo ga aru)
  • I have a little sister.
    (imouto ga iru)

Also, いる (iru) can be combined with a verb in the て (te) form to show continues action.

  • I’m reading a book.
    (hon o yonde iru)

desu – Is That All?

Well, there are some more forms that you could check out, like the volitional だろう (darou) and でしょう (deshou), but I don’t want to give you too much information all at once. So I’ll just leave you with one final example:

  • What can I do for you?
    (nan deshou ka)

Alright, and for the final piece of knowledge, です (desu) is actually the #14 most used word in Japanese. I looked it up!

Let me know what you guys think. Was that too confusing? Did it all make sense? Leave me a comment below!


  • Miqa

    Hello Nick, thanks for your post about “desu”. I think you have a good way of explaining things in the article and some good written examples too. 

    For me who speaks two languages besides English (Swedish and Finnish), but is still new to Japanese, it would have been very interesting to have some audio included as well. 😉 That’s all from me. Keep up the good work!

    • Nick Hoyt

      Hey Miqa! That’s pretty impressive with the amount of different languages that you speak! 

      Yeah on some posts I like to upload audio files, or embed YouTube videos, to help people understand how certain phrases sound. But I don’t always do it depending on what the topic is. This post was more aimed to understanding “desu” from a grammar point of view. 

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