diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 5410bfd2..a49f4c4b 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -25,7 +25,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.10", "3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
         sphinx: [">=8,<9"]
         os: [ubuntu-latest]
         include:
@@ -46,6 +46,7 @@ jobs:
       uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
+        allow-prereleases: true
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
diff --git a/pyproject.toml b/pyproject.toml
index 4ea84ba9..9487e6cd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,6 +18,7 @@ classifiers = [
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
     "Programming Language :: Python :: Implementation :: CPython",
     "Programming Language :: Python :: Implementation :: PyPy",
     "Topic :: Software Development :: Libraries :: Python Modules",
diff --git a/tox.ini b/tox.ini
index ea724631..8c4e286f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -16,7 +16,7 @@ envlist = py310-sphinx8
 [testenv]
 usedevelop = true
 
-[testenv:py{310,311,312}-sphinx{7,8}]
+[testenv:py{310,311,312,313}-sphinx{7,8}]
 deps =
     sphinx7: sphinx>=7,<8
     sphinx8: sphinx>=8,<9