diff --git a/.github/workflows/test-coverage.yaml b/.github/workflows/test-coverage.yaml
new file mode 100644
index 0000000..447d41c
--- /dev/null
+++ b/.github/workflows/test-coverage.yaml
@@ -0,0 +1,74 @@
+# Workflow derived from https://github.com/r-lib/actions/tree/v2/examples
+# Need help debugging build failures? Start at https://github.com/r-lib/actions#where-to-find-help
+on:
+  push:
+    branches: [main, master]
+  pull_request:
+
+name: test-coverage.yaml
+
+permissions: read-all
+
+jobs:
+  test-coverage:
+    runs-on: ubuntu-latest
+    env:
+      GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: r-lib/actions/setup-r@v2
+        with:
+          use-public-rspm: true
+
+      - uses: r-lib/actions/setup-r-dependencies@v2
+        with:
+          extra-packages: any::covr, any::xml2
+          needs: coverage
+
+      - name: Test coverage
+        run: |
+          cov <- covr::package_coverage(
+            quiet = FALSE,
+            clean = FALSE,
+            install_path = file.path(normalizePath(Sys.getenv("RUNNER_TEMP"), winslash = "/"), "package"),
+            function_exclusions = c(
+              "feature_effects\\.ranger",
+              "feature_effects\\.explainer",
+              "feature_effects\\.H2OModel",
+              "partial_dependence\\.ranger",
+              "partial_dependence\\.explainer",
+              "partial_dependence\\.H2OModel",
+              "ale\\.ranger",
+              "ale\\.explainer",
+              "ale\\.H2OModel",
+              "\\.onLoad"
+            )
+          )
+          print(cov)
+          covr::to_cobertura(cov)
+        shell: Rscript {0}
+
+      - uses: codecov/codecov-action@v5
+        with:
+          # Fail if error if not on PR, or if on PR and token is given
+          fail_ci_if_error: ${{ github.event_name != 'pull_request' || secrets.CODECOV_TOKEN }}
+          files: ./cobertura.xml
+          plugins: noop
+          disable_search: true
+          token: ${{ secrets.CODECOV_TOKEN }}
+
+      - name: Show testthat output
+        if: always()
+        run: |
+          ## --------------------------------------------------------------------
+          find '${{ runner.temp }}/package' -name 'testthat.Rout*' -exec cat '{}' \; || true
+        shell: bash
+
+      - name: Upload test results
+        if: failure()
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-test-failures
+          path: ${{ runner.temp }}/package
diff --git a/README.md b/README.md
index 18879f5..4404d4e 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,7 @@
 <!-- badges: start -->
 
 [![R-CMD-check](https://github.com/mayer79/effectplots/actions/workflows/R-CMD-check.yaml/badge.svg)](https://github.com/mayer79/effectplots/actions/workflows/R-CMD-check.yaml)
+[![Codecov test coverage](https://codecov.io/gh/mayer79/effectplots/graph/badge.svg)](https://app.codecov.io/gh/mayer79/effectplots)
 [![CRAN_Status_Badge](https://www.r-pkg.org/badges/version/effectplots)](https://cran.r-project.org/package=effectplots)
 
 <!-- badges: end -->