There's no tool I'm aware of, but with experimental features enabled in the Docker CLI you can use `docker manifest inspect` on each image manifest and diff the content. e.g. `docker manifest inspect ubuntu:latest`.

This requires that you have logged in to the registry, pushed the image to the registry and have `docker pull` rights for the image. You could also run a registry locally, push your image there and inspect your registry's storage db. There's just no CLI command to do that.

This used to be a tool to do it, but it hasn't been kept up to date with changes to image creation and storage. https://imagelayers.io

Beyond Compare for Docker/Moby seems like an ideal use case for an inspection tool such as this. While space is cheap finding dbs which could be consolidated could have some tangible benefits for just about everyone.