Use this MarkDown snippet to add a GitHub Actions status badge to your repo's readme:


You can use GitHub to generate the badge for you. Go to your latest workflow run, click on the triple-dot menu and select Create status badge.
For more information about GitHub Actions workflows, see github-actions.
This one is a little tricky, at the GitHub Pages pipeline is hidden and as such
provides no control over its file name or workflow name (name
in the YAML).
I found it using the Actions tab, finding the GitHub Pages workflow, using the triple-dot menu and its Create Status Badge item. That UI generates the correct URL regardless of the pipeline type.
