diff --git a/src/Illuminate/Validation/Concerns/ValidatesAttributes.php b/src/Illuminate/Validation/Concerns/ValidatesAttributes.php
index b8fb2b1ac589..20e760080786 100644
--- a/src/Illuminate/Validation/Concerns/ValidatesAttributes.php
+++ b/src/Illuminate/Validation/Concerns/ValidatesAttributes.php
@@ -761,7 +761,7 @@ protected function failsRatioCheck($parameters, $width, $height)
             [1, 1], array_filter(sscanf($parameters['ratio'], '%f/%d'))
         );
 
-        $precision = 1 / (max($width, $height) + 1);
+        $precision = 1 / (max(($width + $height) / 2, $height) + 1);
 
         return abs($numerator / $denominator - $width / $height) > $precision;
     }
diff --git a/tests/Validation/ValidationValidatorTest.php b/tests/Validation/ValidationValidatorTest.php
index 942dff373d03..f3d1d3691359 100755
--- a/tests/Validation/ValidationValidatorTest.php
+++ b/tests/Validation/ValidationValidatorTest.php
@@ -4922,6 +4922,13 @@ public function testValidateImageDimensions()
         // Ensure validation doesn't erroneously fail when ratio doesn't matches
         $v = new Validator($trans, ['x' => $uploadedFile], ['x' => 'dimensions:ratio=1']);
         $this->assertFalse($v->passes());
+
+        // Knowing that demo image5.png has width = 1366 and height = 768
+        $uploadedFile = new UploadedFile(__DIR__.'/fixtures/image5.png', '', null, null, true);
+        $trans = $this->getIlluminateArrayTranslator();
+
+        $v = new Validator($trans, ['x' => $uploadedFile], ['x' => 'dimensions:ratio=16/9']);
+        $this->assertTrue($v->passes());
     }
 
     public function testValidateMimetypes()
diff --git a/tests/Validation/fixtures/image5.png b/tests/Validation/fixtures/image5.png
new file mode 100644
index 000000000000..07f80a45d2e4
Binary files /dev/null and b/tests/Validation/fixtures/image5.png differ