diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 19cc9d2..7dc3aef 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,7 +17,7 @@ jobs:
     name: Check Formatting Errors
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Install Dependencies
         run: |
           python -m pip install pycodestyle autopep8
@@ -41,7 +41,7 @@ jobs:
         shell: bash -el {0}
     name: ${{ matrix.os }} Python ${{ matrix.python-version }} Subtest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Setup Miniforge Python ${{ matrix.python-version }}
         uses: conda-incubator/setup-miniconda@v3
         with:
@@ -84,7 +84,7 @@ jobs:
     if: ${{ github.ref == 'refs/heads/main' && github.repository == 'JacksonBurns/py2opsin'}}
     needs: ci-report-status
     steps:
-    - uses: actions/checkout@master
+    - uses: actions/checkout@v4
     - name: Set up Python 3.10
       uses: actions/setup-python@v3
       with: