He is considered among the most significant Florentine biographers/historians of the artists and the arts of the Baroque period. Patronised by the Medici, he aspired to become the new Vasari by renewing and expanding his biographies of artists, to which Baldinucci added lives of French and Flemish artists omitted by Vasari. His most important work was this biographical dictionary of artists, Notizie de' professori del disegno da Cimabue in qua, of which the publication began in 1681 and continued after his death.
His essential biography of Gian Lorenzo Bernini was published in 1682.
Baldinucci came from a prominent and wealthy family of the Florentine merchant elite. As well as writing he drew portraits in chalk and modeled in clay; many of his deft and lively chalk portraits of friends are in the collection of the Uffizi. For Cardinal Leopoldo de' Medici, brother of Ferdinando II de' Medici, Grand Duke of Tuscany and a scholar and patron of the arts, he began as bookkeeper in 1664 and developed, after the Cardinal's death, into virtually the curator of the Grand Ducal collections. In this way Baldinucci made a name as one of Italy's leading connoisseurs. His work recataloguing and adding to the Medici collections, first of drawings and then of paintings, was groundbreaking, using new ideas about organisation and completeness to make these the most modern collections of the time—collections in large part the foundation of the Uffizi's art holdings.
This meticulous work was based on an ability to distinguish between the hands of different painters—an idea then new and untested, and one that opened up the field of connoisseurship that enabled the attributions of Italian drawings, which are generally unsigned. In his Vocabolario, the first dictionary of artistic terms, Baldinucci provided fourteen definitions of style using eighty different terms, and applied some of his terms to "bad" art.
From this grew his Notizie, in which he consciously intended to build upon the Vite of Giorgio Vasari; Baldinucci's was the first art history to trace the lives and work of artists not only of one region (Vasari was predjudiced towards Tuscan artists) but all Italy, and indeed beyond. He studied closely the stylistic debts of the great masters to one another, and in this, and his meticulous use of documentation and archives, he was centuries ahead in the discipline of art history.
In other ways Baldinucci was very much a man of his time, of the Counter-Reformation and of the Baroque. Educated at a Jesuit school, he was intensely pious—before marrying, he completed the whole of Ignatius of Loyola's Spiritual Exercises to discover whether he should in fact devote himself to a single life. Three of his sons went into the church, and one, Antonio, was a Jesuit missionary later beatified.
He had great appreciation of the Baroque, and wrote in a periodic style which reflected it, each phrase opening from the preceding, full of periphrasis and other flourishes of rhetoric, though flowing. His understanding of art stemmed largely from his religion, for he believed that it came as divine inspiration into special lives, the lives of the artists he so painstakingly recorded.
Baldinucci's son wrote the first biography of his father; Baldinucci's notes are conserved in the Biblioteca Nazionale Centrale, Florence (MSS Fondo Nazionale II.II.110)