Replace <input_iso> with the path to your PSX game ISO and <output_chd> with the desired output CHD file name.
A full US PSX library is about 600GB in BIN/CUE. Converted to CHD, it fits on a . You can keep 2-3x more games. psx chd
psxchd <input_iso> <output_chd>
for /r %i in (*.cue) do chdman createcd -i "%i" -o "%~ni.chd" Replace <input_iso> with the path to your PSX