All computations that use floating-point arithmetic are built on the fundamental assumption that the computation is meaningful when employing only a limited precision. The required precision typically varies throughout the computation and depends on the actual represented values. Many computations use too many bits of precision, which reduces performance and increases energy consumption. The Entrans project aims to utilize the optimal precision during a computation without loss of accuracy, which will result in higher execution speed and lower energy consumption. This idea, dubbed transprecision computing, requires novel results in numerical analysis and runtime decision making to adapt the precision of a computation on the fly. The results from this project will benefit society by extending battery life of mobile phones; by saving energy for satellite navigation systems or by enhancing scalability of numerical simulations performed in high-performance computing facilities.