Formalization of mathematics is the process by which pen-and-paper mathematics is translated into a strict chain of logical deductions down to the axioms of mathematics. The subject has seen renewed interest in the last decades, thanks to the development of computer systems, called proof assistants, which make this feasible in practice. There have now been several examples of high-profile mathematical results which have been formalized. In principle any mathematical domain is accessible, but existing projects are skewed towards algebra instead of analysis. Notable exceptions are a project which formalized enough of Gromov’s convex integration theory to deduce Smale’s sphere eversion theorem, and the ongoing project to formalize Carleson’s convergence theorem for Fourier series. This workshop will bring together formalization experts and interested mathematicians to give a new impulse to formalization of analysis (in a very broad sense), and to develop abstractions and tools to deduplicate effort.