On this page, you can transpose the key of your music file online.
You can shift the pitch up and down by a semitone like karaoke.

This page is useful when it's hard to sing a song because that the key of its karaoke(accompaniment) sound does not match for you.

The feature can also be useful to transpose(change the pitch of the notes) music just for enjoying the tune in a different atmosphere.

For an unusual use, it can also be used as a voice changer by converting a person's speaking voice.
In that case, the voice may become high or low depending on the pitch of the key.

Supported file formats are mp3 and aac(m4a/mp4).
＊This function currently support only audio file. Video files are not supported.