Dive is a command line gui tool that lets users explore the layers of a Docker image. The tool shows Docker image contents broken down by layer including changes in a specific layer or aggregated changes up to this layer.
Dive also provides a measure for what the developers call "image efficiency" including a guess how much wasted space an image contains. This might be from duplicating files across layers, moving files across layers, or not fully removing files. Both a percentage "score" and total wasted file space are provided.
The tool can be downloaded from the Dive GitHub page.