Ranft started by studying in Geneva, where he was a student of Sordet, A. du Mont and Gustave Courbet, in Paris. It was there that he published colour engravings and posters. He lived and worked mainly in Coubert. Ranft was a member, in Paris, of the Salon de la Société des Beaux-Arts, and featured at the Salon des Indépendants. In 1910, he exhibited in Paris at the Galerie Chaine et Simonson.