diff --git a/netjsonconfig/backends/openwrt/openwrt.py b/netjsonconfig/backends/openwrt/openwrt.py
index b7d49034c..b288206f1 100644
--- a/netjsonconfig/backends/openwrt/openwrt.py
+++ b/netjsonconfig/backends/openwrt/openwrt.py
@@ -7,7 +7,7 @@
 
 import six
 from jinja2 import Environment, PackageLoader
-from jsonschema import validate
+from jsonschema import FormatChecker, validate
 from jsonschema.exceptions import ValidationError as JsonSchemaError
 
 from . import renderers
@@ -130,7 +130,7 @@ def _render_files(self):
 
     def validate(self):
         try:
-            validate(self.config, self.schema)
+            validate(self.config, self.schema, format_checker=FormatChecker())
         except JsonSchemaError as e:
             raise ValidationError(e)
 
diff --git a/netjsonconfig/schema.py b/netjsonconfig/schema.py
index 9d727175d..5f57a210e 100644
--- a/netjsonconfig/schema.py
+++ b/netjsonconfig/schema.py
@@ -629,6 +629,7 @@
                     "type": "string",
                     "maxLength": 63,
                     "minLength": 1,
+                    "format": "hostname",
                     "propertyOrder": 1,
                 },
                 "ula_prefix": {
diff --git a/tests/openwrt/test_formats.py b/tests/openwrt/test_formats.py
new file mode 100644
index 000000000..4f21e172d
--- /dev/null
+++ b/tests/openwrt/test_formats.py
@@ -0,0 +1,17 @@
+import unittest
+
+from netjsonconfig import OpenWrt
+from netjsonconfig.exceptions import ValidationError
+from netjsonconfig.utils import _TabsMixin
+
+
+class TestFormats(unittest.TestCase, _TabsMixin):
+    maxDiff = None
+
+    def test_general_hostname(self):
+        o = OpenWrt({"general": {"hostname": "invalid hostname"}})
+        with self.assertRaises(ValidationError):
+            o.validate()
+        o.config['general']['hostname'] = 'valid'
+        o.validate()
+