TIGRE: Tomographic Iterative GPU-based Reconstruction Toolbox. TIGRE is a MATLAB and Python/CUDA toolbox for fast and accurate 3D tomographic reconstruction (any geometry), created jointly by University of Bath’s Engineering Tomography Lab and CERN. The aim of TIGRE is to provide a wide range of easy-to-use iterative algorithms to the tomographic research community. We would like to build an stronger bridge between algorithm researchers and imaging researchers, by encouraging and supporting contributions from both sides into TIGRE.