How to get exact date for docker images?

Use docker inspect:

docker inspect -f '{{ .Created }}' IMAGE_OR_CONTAINER

From: Exact times in "docker ps" and "docker images"

You can use the --format parameter to output CreatedAt instead of CreatedSince:

docker images --format "table {{.Repository}}\t{{.Tag}}\t{{.ID}}\t{{.CreatedAt}}\t{{.Size}}"

See the command line reference for more info.

I think the best way would be to run docker inspect IMAGE_OR_CONTAINER, then pipe the output to grep to filter the results to what you really want.

If you only want to know when it started, run

docker inspect IMAGE_OR_CONTAINER | grep -i created

... which results in the following output:

"Created": "2015-09-18T01:46:51.471641483Z",

That's pretty clean.

... you could do the same for "started":

docker inspect IMAGE_OR_CONTAINER | grep -i started

... which results in the following output:

"StartedAt": "2015-09-18T01:46:51.79789586Z"

In addition to Dag's answer, you can permanently change the format of the output from docker images by adding your custom format to your ~/.docker/config.json file:

"imagesFormat": "table {{.Repository}}\\t{{.Tag}}\\t{{.ID}}\\t{{.Size}}\\t{{.CreatedAt}}"