HDF5 command line tool h5dump and h5ls are handy to quickly explore HDF5 files from the command line. They are particularly useful when accessing a remote computer such as HPC where the HDF5 files may be very large and would take a while to transfer to a local computer.
h5ls provides a high-level look at objects in an HDF5 file. Typically we start examining HDF5 files like:
h5ls -r my.h5
h5dump can print the entire contents of an HDF5 file to the screen. This can be overwhelming, so we typically print only the headers to start:
h5dump -H my.h5
Individual variables can be printed like:
h5dump -d myvar my.h5
Related: HDF5 data GUI