What it means
てもかまわない expresses permission or acceptance: “it is okay to” do something or “it does not matter if” something is true. It can describe an action that is allowed, or a condition that the speaker accepts without objection. It follows a verb in the te-form, an i-adjective in its ku-form plus ても, or a noun or na-adjective plus でも. The familiar form is てもかまわない, while the polite counterpart is てもかまいません.
Usage note
てもかまわない is grammatically correct but can sound more formal or deliberate than てもいい. With a person, it may sometimes sound as though the person is merely being tolerated, so use it carefully when expressing permission directly to someone.
How to use it
応募者は学生でもかまいません。
It is okay if the applicant is a student.
この会場は静かでもかまいません。
It is okay if this venue is quiet.
この薬は苦くてもかまいません。
It is okay if this medicine is bitter.
この部屋で写真を撮ってもかまいません。
It is okay to take photos in this room.
応募者は学生でもかまわない。
It is okay if the applicant is a student.
この会場は静かでもかまわない。
It is okay if this venue is quiet.
この薬は苦くてもかまわない。
It is okay if this medicine is bitter.
この部屋で写真を撮ってもかまわない。
It is okay to take photos in this room.