CAVE-CL: an OpenCL version of the package for detection and quantitative analysis of internal cavities in a system of overlapping balls: application to proteins. Here we present the revised and newly rewritten version of our earlier published CAVE package [the second author et al., ibid. 181, No. 12, 2116–2125 (2010; Zbl 1216.92034)] which was originally written in FORTRAN. The package has been rewritten in C language, the algorithm has been parallelized and implemented using OpenCL. This makes the program convenient to run on platforms with Graphical Processing Units (GPUs). Improvements include also some modifications/optimizations of the original algorithm. A considerable improvement in the performance of the code has been achieved. A new tool called input_structure has been added which helps the user to make the data input and conversion more easier and universal.