diff --git a/.github/workflows/image.yml b/.github/workflows/image.yml
index 03a055a7..5143e8ed 100644
--- a/.github/workflows/image.yml
+++ b/.github/workflows/image.yml
@@ -19,7 +19,7 @@ jobs:
 
       - name: Build image
         run: |
-          IMAGE_ID=docker.pkg.github.com/${{ github.repository }}:${{ github.branch }}
+          IMAGE_ID=docker.pkg.github.com/${{ github.repository }}:${GITHUB_REF#refs/heads/}
           docker build . -f Dockerfile --tag $IMAGE_ID
           docker push $IMAGE_ID
           echo Pushed new build image $IMAGE_ID