diff --git a/tests_app/settings.py b/tests_app/settings.py
index 334d9ef..1d3dee8 100644
--- a/tests_app/settings.py
+++ b/tests_app/settings.py
@@ -161,3 +161,5 @@
     'django.contrib.auth.backends.ModelBackend',  # this is default
     'guardian.backends.ObjectPermissionBackend',
 )
+
+DEFAULT_AUTO_FIELD = 'django.db.models.AutoField'
diff --git a/tox.ini b/tox.ini
index 770a4d1..2427c3a 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,26 +1,22 @@
 [tox]
-envlist = py{37,38,39}-django{22}-drf{39,310,311,312}
-          py{37,38,39}-django{30}-drf{310,311,312}
-          py{37,38,39}-django{31}-drf{311,312}
-          py{37,38,39}-django{32}-drf{312}
+envlist = py{38,39}-django{22}-drf{311,312}
+          py{38,39}-django{32}-drf{312,313,314}
 
 
 [testenv]
 deps=
     -rtests_app/requirements.txt
     django-guardian>=1.4.4
-    drf39: djangorestframework>=3.9.3,<3.10
-           djangorestframework-guardian
-    drf310: djangorestframework>=3.10,<3.11
-           djangorestframework-guardian
     drf311: djangorestframework>=3.11,<3.12
            djangorestframework-guardian
     drf312: djangorestframework>=3.12,<3.13
            djangorestframework-guardian
+    drf313: djangorestframework>=3.13,<3.14
+           djangorestframework-guardian
+    drf314: djangorestframework>=3.14,<3.15
+           djangorestframework-guardian
     django22: Django>=2.2,<3.0
-    django30: Django>=3.0,<3.1
-    django31: Django>=3.1,<3.2
-    django32: Django>=3.2
+    django32: Django>=3.2,<4.0
 setenv =
     PYTHONPATH = {toxinidir}:{toxinidir}/tests_app
 commands =