diff --git a/src/pretix/api/migrations/0006_alter_webhook_target_url.py b/src/pretix/api/migrations/0006_alter_webhook_target_url.py
new file mode 100644
index 0000000000..1185b81228
--- /dev/null
+++ b/src/pretix/api/migrations/0006_alter_webhook_target_url.py
@@ -0,0 +1,18 @@
+# Generated by Django 3.2.2 on 2021-07-05 07:56
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixapi', '0005_auto_20191028_1541'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='webhook',
+            name='target_url',
+            field=models.URLField(max_length=255),
+        ),
+    ]
diff --git a/src/pretix/api/models.py b/src/pretix/api/models.py
index 95fba64797..dd6bbe589e 100644
--- a/src/pretix/api/models.py
+++ b/src/pretix/api/models.py
@@ -95,7 +95,7 @@ class OAuthRefreshToken(AbstractRefreshToken):
 class WebHook(models.Model):
     organizer = models.ForeignKey('pretixbase.Organizer', on_delete=models.CASCADE, related_name='webhooks')
     enabled = models.BooleanField(default=True, verbose_name=_("Enable webhook"))
-    target_url = models.URLField(verbose_name=_("Target URL"))
+    target_url = models.URLField(verbose_name=_("Target URL"), max_length=255)
     all_events = models.BooleanField(default=True, verbose_name=_("All events (including newly created ones)"))
     limit_events = models.ManyToManyField('pretixbase.Event', verbose_name=_("Limit to events"), blank=True)