Below find an overview over all the Japanese verb conjugations, including all irregular verbs. For more specific information on how each conjugation is used refer to the appropriate links.

In modern Japanese, two types of words are conjugated
  1. Verbs
  2. Verbal Adjectives
Verbs have five conjugations in modern Japanese, verbal adjectives four:

  1. Rentaikei (attributive form)
  2. Ren’youkei (continuative form): this conjugation has many contractions. If you are unable to identify the conjugation, you are probably dealing with the ren’youkei.
  3. Izenkei
  4. Mizenkei (negative, subjunctive, causative, and passive forms): verbs ending on “-ou” have the mizenkei as conjugation.
  5. Meireikei (imperative form): verbs only.
Verbs

Verbs are divided into two groups, known as Group 2 verbs (nidan katsu you 二段活用) and Group 4 verbs (yodan katsu you 四段活用). Each group has its conjugations. There are two irregular verbs and a group of five honorific verbs that have two irregular conjugations.

Verbs belong to Group 2 when the rentaikei conjugation ends on “-eru” or “-iru”.

There is a further distinction between these two as the lower Group 2, or shimo nidan katsu you (下二段活用), ending on “-eru”; and the higher Group 2, or kami nidan katsu you (上二段活用), ending on “-iru”, but for all practical purposes there is no difference between the two.

Group 2 conjugationsto eatto see
Rentaikei 連体形食べるtaberu見る miru
Ren'youkei 連用形食べ tabe見 mi
Izenkei 已然形食べれ tabere 見れ mire
Mizenkei 未然形食べ tabe 見 mi
Meireikei 命令形 食べよ/ろ tabe yo/ro見よ/ろ mi yo/ro


Note: There are verbs belonging to Group 4 where the rentaikei conjugation ends on “-iru” or “-eru”. All other verbs belong to Group 4.

Group 4 conjugationsto writeto buyto waitto lend
Rentaikei 連体形書く kakukau 待つ待つ matsu貸す kasu
Ren'youkei 連用形書き kakikai 待ち待ち machi貸し kashi
Izenkei 已然形書け kake買え kae 待て待て mate貸せ kase
Mizenkei 未然形書か kaka買わ kawa待た mata貸さ kasa
Meireikei 命令形 書け kake買え kae待て mate貸せ kase


Note: Pay special attention to the mizenkei of verbs ending on the hiragana う (u), this conjugation uses the hiragana わ (wa) instead of あ (a).

Irregular verbs

The two truly irregular verbs are “to do” and “to come”:

Irregular verbsto doto come
Rentaikei 連体形する suru来 ki
Ren'youkei 連用形し shikai 待ち
Izenkei 已然形すれ sure来れ kure
Mizenkei 未然形し、せ、さ shi, se, saいい/良い ii/yoi
Meireikei 命令形 しよ/ろ、せよ/ろ、せい shi yo/ro, se yo/ro, sei来い koi


Note: There are various conjugations for the mizenkei for the verb する (suru). し (shi) is reserved for the negative form, せ (se) and さ (sa) is reserved for the causative form and the passive form. Particular attention needs to be paid to the ren’youkei and the mizenkei conjugations of 来る (kuru). Though they are written the same way, their pronunciations are different.

These honorific verbs have irregular ren’youkei and meireikei conjugations. All five verbs follow the same irregular pattern.

Irregular conjugationsto speakto giveto do
Rentaikei 連体形仰る ossharu下さる kudasaru為さる nasaru
Ren'youkei 連用形仰い osshai下さい kudasai為さい nasai
Izenkei 已然形仰れ osshare下され kudasare為され nasare
Mizenkei 未然形仰ら osshara下さら kudasara為さら nasara
Meireikei 命令形 仰い osshai下さい kudasai為さい nasai


Irregular verbsthere is/are / to come/to go (living beings)there is/are (objects)
Rentaikei 連体形いらっしゃる irassharu御座る gozaru
Ren'youkei 連用形いらっしゃい irasshai御座い gozai
Izenkei 已然形いらっしゃれ irasshare御座れ gozare
Mizenkei 未然形いらっしゃら irasshara御座ら gozara
Meireikei 命令形 いらっしゃい irasshai御座い gozai


Verbal Adjectives

Verbal adjectives have only four conjugations in modern Japanese. The meireikei conjugation does not exist. There is one irregular verbal adjective: いい (ii).

Verbal adjectivesto be largeto be newto be good (irregular)
Rentaikei 連体形大きい ōkii新しい atarashiiいい/良い ii/yoi
Ren'youkei 連用形大きく ōkiku新しく atarashikuよく/良く yoku
Izenkei 已然形大きけれ ōkikere新しけれ atarashikereよけれ/良けれ yokere
Mizenkei 未然形大きく ōkiku新しく atarashikuよく/良く yoku
Meireikei 命令形 ---