Conjugation is the variation in the endings of verbs (inflections) depending on the person (I, you, we, etc), tense (present, future, etc.) and mood (indicative, imperative, subjunctive, etc.). Most French verbs are regular and their inflections can be entirely determined by their infinitive form.

French verbs are conventionally divided into three groups. The first two are the -er and -ir conjugations (conjugaisons). Verbs of the first two groups follow the same patterns, largely without exception. The third group displays more variation in form.

The third group is a closed class, meaning that no new verbs of this group are created. Most new verbs are of the first group (téléviser, atomiser, radiographier), with some in the second group (alunir).

In summary the groups are:

The verb forms of French are the finite forms, which are combinations of grammatical moods in various tenses, and the non-finite forms. The moods are: indicative (indicatif), subjunctive (subjonctif), conditional (conditionnel) and imperative (impératif). Tense formation can be either simple (a single, conjugated form), or compound (an auxiliary verb plus a participle, which is not conjugated; see below for details). The finite forms are:

The non-finite forms are:

Both participles may be used as adjectives in which case they are inflected as adjectives. Used as an adjective the present participle is known as the verbal adjective. There are some cases where a form similar but not identical to the present participle is used for the verbal adjective.

There are two auxiliary verbs in French: avoir (to have) and être (to be), used to conjugate compound tenses according to these rules: