diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 1f946e5f..b1d4a1f6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -52,7 +52,7 @@ jobs:
             python-version: 3.6
             tox-env: py36
           - name: py3.7
-            os: ubuntu-latest
+            os: ubuntu-22.04
             python-version: 3.7
             tox-env: py37
           - name: py3.8
@@ -81,14 +81,18 @@ jobs:
             tox-env: py311
           - name: py3.12
             os: ubuntu-latest
-            python-version: '3.12.0-beta.1'
+            python-version: '3.12'
             tox-env: py312
+          - name: py3.13
+            os: ubuntu-latest
+            python-version: '3.13'
+            tox-env: py313
           - name: pypy
             os: ubuntu-latest
             python-version: pypy-2.7
             tox-env: pypy
           - name: pypy3
-            os: ubuntu-latest
+            os: ubuntu-22.04
             python-version: pypy-3.7
             tox-env: pypy3
           # special configurations
@@ -320,7 +324,7 @@ jobs:
           cr-html session-vs-master.sqlite > cosmic-ray.html
       - name: Archive mutation testing results
         if: ${{ matrix.mutation == 'true' && github.event.pull_request }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: mutation-PR-coverage-report
           path: cosmic-ray.html
@@ -661,7 +665,7 @@ jobs:
         run: |
           cr-html session.sqlite > cosmic-ray.html
       - name: Archive mutation testing results
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: mutation-coverage-report
           path: cosmic-ray.html
diff --git a/setup.py b/setup.py
index 341fe734..618f5e6d 100755
--- a/setup.py
+++ b/setup.py
@@ -42,6 +42,7 @@
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",
+        "Programming Language :: Python :: 3.13",
     ],
     install_requires=["six>=1.9.0"],
     extras_require={"gmpy2": "gmpy2", "gmpy": "gmpy"},
diff --git a/tox.ini b/tox.ini
index ea01c4b4..19c03175 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,17 +1,17 @@
 
 [tox]
-envlist = py26, py27, py35, py36, py37, py38, py39, py310, py311, py312, py, pypy, pypy3, gmpy2py27, gmpy2py39, gmpy2py310, gmpypy27, gmpypy39, gmpypy310, codechecks
+envlist = py26, py27, py35, py36, py37, py38, py39, py310, py311, py312, py313, py, pypy, pypy3, gmpy2py27, gmpy2py39, gmpy2py310, gmpypy27, gmpypy39, gmpypy310, codechecks
 
 [testenv]
 deps =
      py{26}: unittest2
      py{26}: hypothesis<3
-     py{26,27,35,36,37,38,39,310,311,312,py,py3}: pytest
-     py{27,35,36,37,38,39,310,311,312,py,py3}: hypothesis
-     gmpy2py{27,39,310,311,312}: gmpy2
-     gmpypy{27,39,310,311,312}: gmpy
-     gmpy{2py27,2py39,2py310,2py311,2py312,py27,py39,py310,py311,py312}: pytest
-     gmpy{2py27,2py39,2py310,2py311,2py312,py27,py39,py310,py311,py312}: hypothesis
+     py{26,27,35,36,37,38,39,310,311,312,313,py,py3}: pytest
+     py{27,35,36,37,38,39,310,311,312,313,py,py3}: hypothesis
+     gmpy2py{27,39,310,311,312,313}: gmpy2
+     gmpypy{27,39,310,311,312,313}: gmpy
+     gmpy{2py27,2py39,2py310,2py311,2py312,2py313,py27,py39,py310,py311,py312,py313}: pytest
+     gmpy{2py27,2py39,2py310,2py311,2py312,2py313,py27,py39,py310,py311,py312,py313}: hypothesis
 # six==1.9.0 comes from setup.py install_requires
      py27_old_six: six==1.9.0
      py27_old_six: pytest
@@ -53,6 +53,9 @@ basepython=python3.11
 [testenv:gmpypy312]
 basepython=python3.12
 
+[testenv:gmpypy313]
+basepython=python3.13
+
 [testenv:gmpy2py27]
 basepython=python2.7
 
@@ -68,6 +71,9 @@ basepython=python3.11
 [testenv:gmpy2py312]
 basepython=python3.12
 
+[testenv:gmpy2py313]
+basepython=python3.13
+
 [testenv:instrumental]
 basepython = python2.7
 deps =