docker history

history

Usage:  docker history [OPTIONS] IMAGE

Show the history of an image

Options:
      --help       Print usage
  -H, --human      Print sizes and dates in human readable format (default true)
      --no-trunc   Don't truncate output
  -q, --quiet      Only show numeric IDs

To see how the docker:latest image was built:

$ docker history docker
IMAGE               CREATED             CREATED BY                                      SIZE                COMMENT
3e23a5875458        8 days ago          /bin/sh -c #(nop) ENV LC_ALL=C.UTF-8            0 B
8578938dd170        8 days ago          /bin/sh -c dpkg-reconfigure locales &&    loc   1.245 MB
be51b77efb42        8 days ago          /bin/sh -c apt-get update && apt-get install    338.3 MB
4b137612be55        6 weeks ago         /bin/sh -c #(nop) ADD jessie.tar.xz in /        121 MB
750d58736b4b        6 weeks ago         /bin/sh -c #(nop) MAINTAINER Tianon G