This post list the commands required to delete a git tag both locally and on the remote server.
Delete Tag Locally
The git command tag -d can be used to delete a tag locally.
# Delete local tag git tag -d <tag name>
# Example - Delete the local tag alpha1 git tag -d alpha1
Delete Tag on Remote Server
The git command push can be used to delete a tag on the remote server as shown below for remote server named origin.
# Delete remote tag git push origin :refs/tags/<tag name>
OR
git push --delete origin <tag name>
# Example - Delete the remote tag alpha1 git push origin :refs/tags/alpha1
OR
git push --delete origin alpha1