What about Hraw? GitHub - lightful/hraw: Hacker's toolkit for image sensor characterisation
In Windows it is a drag and drop feature to check how many % that is clipped. In Linux I use the terminal.
$ dcraw -E -4 -j -t 0 -s all IMG_9106.CR2
$ ./hraw clipping -i IMG_9106_0.pgm -v
If you shoot Canon with ML support you can get the clipping feature already in camera.