This book constitutes the proceedings of the Second International Joint Conference on Quantitative Evaluation of Systems and Formal Modeling and Analysis of Timed Systems, QEST+Formats 2025, which took place in Aarhus, Denmark, during August 2025.The 26 full papers included in these proceedings were carefully reviewed and selected from 57 submissions. They focus on up to date research in quantitative evaluation of systems and formal modeling and analysis of timed systems.