The Japanese Potential Form: A Complete Guide

In English, the potential form of verbs uses the word “can” (can do, can see, etc.). How do you use the potential form in Japanese? 

In this article, we will discuss the different forms and uses of the Japanese potential form and some of the nuances within them.

できる (Dekiru): The Backbone of the Potential Form

All verbs in Japanese can be conjugated into the potential form. The simplest verb, and the most important with which to start, is the potential form of する (suru), the “to do” verb. 

The potential form of する is できる (dekiru), which of course means “can do.” できる can be used in various ways to communicate potential; for example, it can communicate skill or capability when used with a noun. 


(ongaku dattara ore wa gitaa ga dekiru)
If we’re talking about music, I can do (play) the guitar.

Also, できる can be used in its past tense, できた (dekita), to express accomplishment.

(kimatsu shiken ga dekita)
I passed the final exam!

~ことができる (Koto Ga Dekiru):  Formal Potential Form With Verbs

If you want to use the potential form with verbs, one way is to use the present tense form of the verb followed by ことができる. This phrase directly translates to “be able to do ~ing,” where the “ing” is the verb being used. Take a look at the following example sentence for a more in-depth explanation. 


(saki ni sensei ni kiitara, borantia ni sanka suru koto ga dekiru kamoshirenai)
If you ask the teacher ahead of time, maybe you can join in the volunteer event.

The use of 参加することができる implies that the idea of joining in becomes possible upon asking. In other words, ~ことができる is often used when discussing the potential of a concept, rather than physical capability.

Conjugating Verbs into the Potential Form Without Using できる (More Casual)

The words, "I can't" on a white piece of paper with blue ink. A pair of scissors is cutting the "'t" part off of the word can't.

While できる and ~ことができる are common cases of potential form, it is possible to use the potential form without the できる verb. As was previously mentioned, all verbs can be conjugated into the potential form, which we will discuss below.

The conjugation of verbs into their potential form is dependent on which type of verb they are. The main two types are る(ru)-verbs and う(u)-verbs. 

る-Verbs/Group 2 Verbs: Examples

る-verbs are verbs that end in the る hiragana, preceded by either an “e” vowel sound or an “i” vowel sound. These verbs are also known as group 2 verbs.  

  • 食べる (taberu, to eat)
  • 起きる (okiru, to awake)

う-Verbs/Group 1 Verbs: Examples

う-verbs are verbs that end in any other hiragana with a “u” vowel sound and/or have a vowel sound, “u” vowel sound, or “o” vowel sound in their second to last hiragana. These are also known as Group 1 verbs.  

  • 使う (tsukau, to use)
  • 泳ぐ (oyogu, to swim)
  • 飲む (nomu, to drink)
  • 待つ (matsu, to wait)
  • 作る (tsukuru, to make)

る-Verbs (Group 1 Verbs): Potential Form Conjugation

First, let’s discuss how to conjugate る-verbs into their potential form. All る-verbs follow the same conjugation pattern: change “る” to “られる” (rareru).

  • 食べ      → 食べられる (taberareru)
  • 起き      → 起きられる (okirareru)

Once conjugated, you use potential verbs just like plain form (present tense) verbs. The following example sentence makes use of 食べられる. 


(watashi wa washoku ga suki de, wakame mo taberareru)
I like Japanese food, and I can even eat seaweed.

う-Verbs (Group 1 Verbs): Potential Form Conjugation

Moving on, we’ll discuss how to conjugate う-verbs into their potential form. While る-verbs are simple to conjugate, う-verbs require slightly more care to create their potential form. 

For う-verbs, we must first recognize the consonant sound of the final hiragana in the verb. For example, in the verb 泳ぐ, the final hiragana is ぐ (gu), which has the “g” sound. 

To make the potential form, replace the “u” sound in the hiragana with the “e” sound (ぐ becomes げ (ge)), and add る to the end. 

  → 泳げる (oyogeru)

This conjugation process is the same for all う-verbs. The following list provides more examples based on the う-verbs listed above. 

  • 使 → 使える (tsukaeru)
  • → 飲める (nomeru)
  • → 待てる (materu)
  • → 作れる (tsukureru)

う-verbs in their potential form are used in the same way as る-verbs. Take a look at the following example sentence for a clearer picture. 


(umi no chikaku de sodatta kara oyogeru)
I can swim because I grew up near the ocean.

Can’t Do: The Negative Potential Form

Wooden blocks resting on a wooden table that spell "I CANT." Someone's hand is seen on the right side holding the "T" block.

In addition to the ability to communicate capability, communicating a lack of capability is also essential. Potential forms have a negative form in the same way that る-verbs do: replace the る at the end with ない (nai).

  • 食べられ      → 食べられない
  • 泳げ      → 泳げない

This also applies to the verb できる.

● でき      → できない

Take a look at the following example sentences to see how negative potential form works in context.


1. 英語ならできるけど、スペイン語まではできない。
(eigo nara dekiru kedo, supeingo made wa dekinai)
I can speak English, but I can’t speak Spanish.

2. ヒロシはまだ小1だから簡単な足し算ならできるけど、かけ算はできないよ。
(hiroshi wa mada shouichi dakara kantan na tashizan nara dekiru kdeo, kakezan wa dekinai yo)
Since Hiroshi is only a 1st grader he can do simple addition, but can’t do multiplication.

3. 彼に嘘つくことができないよ、悪いから。
(kare ni uso tsuku koto ga dekinai yo, warui kara)
I can’t lie to him; I feel bad.

4. すみません、やっぱり納豆が食べられない。
(sumimasen, yappari natto ga taberarenai)
I’m sorry, but I can’t eat natto.

Shortening the る-Verb Potential Form

In the case of る-verbs, the addition of られる can cause the potential form to become longer than other conjugations, and in some cases, more challenging to pronounce. Thus, the “ら” is sometimes dropped, and the る-verb conjugation becomes similar to う-verbs. 

食べれる – ” ら” = 食べれる

However, it’s important to remember that this is not used in writing and is only found when speaking casual Japanese. This short form is technically wrong, but it is very commonly used in casual, everyday conversations.  


(mochiron uni tabereru yo, umai kara)
Of course I can eat sea urchin, it’s delicious!

The above example sentence is very casual Japanese, but it shows an example where shortening the る-verb potential form would be typical. 

Polite Potential Form

Two Asian men dressed in suits and shaking each other's hand.  A woman in a black and white business outfit is on the right of the two men.

So far, every example we have used to explain the potential form has used the casual form of the verb, which ends in る. However, there is also a polite form of these verbs, most often used in formal or business situations. Every example above can be recreated using the polite potential form. 

To start, the polite form of 出来る is 出来ます (dekimasu). This form can be used both by itself and in the ことができる phrase. 


1. あちらの窓口で日本円に両替出来ます。
(achira no mado guchi de nihon en ni ryougae dekimasu)
You can exchange to Japanese yen at the window over there.

2. ブランケットをご用意することができます。
(buranketto wo goyoui suru koto ga dekimasu)
We can prepare a blanket.

For る-verbs and う-verbs, replace the “る” at the end of the potential form with ます (masu).

3. 私たちは皆生魚を食べられますので大丈夫です。
(watashitachi wa minna namazakana o taberaremasu no de daijobu desu)
We all can eat raw fish, so there is no problem.

4. プールで10ラップを泳げます。
(puru de ju rappu o oyogemasu)
I can swim 10 laps in the pool.

The が (Ga) Particle

You may have noticed that most of the above examples use the particle が (ga) when connecting the verb to a noun. While を (o) is used generally for transitive verbs, when using the potential form, the が particle is more common. 

(nihongo o hanasu)
I speak Japanese

(nihongo ga hanaseru)
I can speak Japanese

In some cases, either を or が can be used interchangeably, such as in the following example. 

○ 納豆を食べられる

○ 納豆が食べられる

However, for the verb できる, only が is used. 

○ 日本語ができる

× 日本語をできる

If you are unsure which particle to use, it is usually safer to use が. 


Mastering the potential form in Japanese will take your conversations to another level. It is very common to use this form in everyday conversations, and I’m sure you’ll find it very useful. Keep doing your best, and remember, you can do it!

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Andrew Garrison

A writer and translator currently living in Nagasaki. In love with all things to do with words, from stories and languages to poetry.

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