The Cathedral's dome has 44 windows constitute the most extensive stained glass program in 14th and 15th-century Italy.

The windows depict Old and New Testament situations , and scenes about the life of Christ and Mary. The list of artists is long from early Renaissance: Donatello, Ghiberti, Paolo Uccello and Andrea del Castagno.
From the crossing, under the dome, and the iconological purpose of the window program becomes apparent: to evoke the spiritual light in Christ. The New Testament claims, in fact, that in Christ was life.

List of scenes: The Elders of Revelation; Angelic Choirs with the Instruments of Christ's Passion; Christ, Mary and the Saints; Virtues, Beatitudes and Gifts of the Holy Spirit; Vices and Hell; Windows in the drum; Donatello - Coronation of Mary; Paolo Uccello, Resurrection of Christ. - Andrea del Castagno, Deposition; Paolo Uccello, Nativity of Christ. Paolo Uccello, Annunciation. - Lorenzo Ghiberti, Presentation in the Temple. - Lorenzo Ghiberti, Agony in the Garden - Lorenzo Ghiberti, Ascension.