His style merges the everyday subjects of the Roman street with a refined, classical execution. While his contemporaries often painted common scenes with a sense of caricature, Sweerts treated his subjects with quiet dignity. Works such as Man Holding a Jug or Boy Removing a Gentleman's Shoe use a cool, silvery light that creates a sense of stillness. He often focused on the act of learning or simple labour, using a palette dominated by greys and muted earth tones.

Modern collectors value Sweerts for the psychological depth and lack of artifice in his portraits. His compositions avoid the aggressive drama common in Baroque art, preferring a calm atmosphere that suits contemporary living spaces. The subjects appear caught in moments of private reflection. This humanistic approach makes his prints suitable for modern collections, as they depict seventeenth-century life with clarity.