diff --git a/zerver/lib/validator.py b/zerver/lib/validator.py
index 210578fcc7..4d113b466f 100644
--- a/zerver/lib/validator.py
+++ b/zerver/lib/validator.py
@@ -105,7 +105,7 @@ def check_bool(var_name: str, val: object) -> Optional[str]:
 def check_color(var_name: str, val: object) -> Optional[str]:
     if not isinstance(val, str):
         return _('%s is not a string') % (var_name,)
-    valid_color_pattern = re.compile(r'^#(?:[a-fA-F0-9]{6})$')
+    valid_color_pattern = re.compile(r'^#([a-fA-F0-9]{3,6})$')
     matched_results = valid_color_pattern.match(val)
     if not matched_results:
         return _('%s is not a valid hex color code') % (var_name,)
diff --git a/zerver/tests/test_decorators.py b/zerver/tests/test_decorators.py
index a609f3c2ef..ad9d60db62 100644
--- a/zerver/tests/test_decorators.py
+++ b/zerver/tests/test_decorators.py
@@ -772,7 +772,7 @@ class ValidatorTestCase(TestCase):
         self.assertEqual(check_float('x', x), 'x is not a float')
 
     def test_check_color(self) -> None:
-        x = ['#000099', '#80ffaa', '#80FFAA', '#abcd12']  # valid
+        x = ['#000099', '#80ffaa', '#80FFAA', '#abcd12', '#ffff00', '#ff0', '#f00']  # valid
         y = ['000099', '#80f_aa', '#80fraa', '#abcd1234', 'blue']  # invalid
         z = 5  # invalid