Japanese Verb Conjugator & Verb Forms Generator

How do I conjugate a Japanese verb from its dictionary form?

Type the dictionary form into the tool and it will generate every standard inflection at once — Masu, Te, Nai, Past, Potential, Passive, and Causative — instead of you deriving each one by hand. The tool first classifies the verb as Godan, Ichidan, or Irregular, because the conjugation pattern for every form depends entirely on that classification.

What is the Te-form of 行く (iku), and why doesn't it follow the usual Godan pattern?

行く is a Godan verb ending in く, so the regular rule would produce 行いて. In practice, 行く is an irregular exception and its Te-form is 行って (with a small っ), matching the sound-change pattern of Godan verbs ending in う, つ, or る instead of く. This is one of the few sound-change exceptions worth memorizing individually, and the tool applies it automatically rather than the regular く-ending rule.

What verb forms does this tool generate?

For every verb it generates the Masu form (polite non-past), Nai form (plain negative), Te form (connective), Ta form (plain past), Nakatta form (plain past negative), Potential form (can-do), Passive form, Causative form, and the plain/dictionary form used as the base. Irregular verbs (する, くる) get their own hard-coded tables since they don't follow Godan or Ichidan rules.

How do I convert a verb to its polite Masu form?

Enter the dictionary form and the tool derives Masu form based on verb type: Godan verbs change the final u-sound to the corresponding i-sound before adding ます (飲む → 飲みます), Ichidan verbs drop る and add ます (食べる → 食べます), and irregular verbs use their fixed forms (する → します, くる → きます).

How can I tell if a verb is Godan or Ichidan?

Verbs ending in -eru or -iru are usually Ichidan (like 食べる, 見る), which drop る and attach the ending directly. Verbs ending in any other u-sound are Godan, which shift across the five vowel rows (う段) before attaching endings. The catch is exceptions like 帰る, 入る, and 走る — they end in -eru/-iru but conjugate as Godan. The tool auto-detects verb type but lets you override it manually for these known exceptions.