diff --git a/src/Optimizely/Utils/Validator.php b/src/Optimizely/Utils/Validator.php
index 5b8dd7e0..7f10c2f1 100644
--- a/src/Optimizely/Utils/Validator.php
+++ b/src/Optimizely/Utils/Validator.php
@@ -70,17 +70,52 @@ public static function areAttributesValid($attributes)
         return count(array_filter(array_keys($attributes), 'is_string')) > 0;
     }
 
+    /**
+     * @param $value The value to validate.
+     *
+     * @return boolean Representing whether attribute's value is
+     * a number and not NAN, INF, -INF or greater than absolute limit of 2^53.
+     */
+    public static function isFiniteNumber($value)
+    {
+        if (!(is_int($value) || is_float($value))) {
+            return false;
+        }
+       
+        if (is_nan($value) || is_infinite($value)) {
+            return false;
+        }        
+
+        if (abs($value) > pow(2, 53)) {
+            return false;
+        }
+
+        return true;
+    }
+
     /**
      * @param $attributeKey The key to validate.
      * @param $attributeValue The value to validate.
      *
      * @return boolean Representing whether attribute's key and value are
-     * valid for event payload or not.
+     * valid for event payload or not. Valid attribute key must be a string.
+     * Valid attribute value can be a string, bool, or a finite number.
      */
     public static function isAttributeValid($attributeKey, $attributeValue)
     {
-        $validTypes = array('boolean', 'double', 'integer', 'string');
-        return is_string($attributeKey) && in_array(gettype($attributeValue), $validTypes);
+        if (!is_string($attributeKey)) {
+            return false;
+        }
+
+        if (is_string($attributeValue) || is_bool($attributeValue)) {
+            return true;
+        }
+
+        if (is_int($attributeValue) || is_float($attributeValue)) {
+            return Validator::isFiniteNumber($attributeValue);
+        }
+
+        return false;
     }
 
     /**
diff --git a/tests/UtilsTests/ValidatorTest.php b/tests/UtilsTests/ValidatorTest.php
index 715b54a9..8ecf8e87 100644
--- a/tests/UtilsTests/ValidatorTest.php
+++ b/tests/UtilsTests/ValidatorTest.php
@@ -123,6 +123,34 @@ public function testisAttributeValidAttributeWithInValidKeyValue()
         $this->assertFalse(Validator::isAttributeValid(5.5, 'value'));
     }
 
+    public function testIsFiniteNumberWithInvalidValues()
+    {
+        $this->assertFalse(Validator::IsFiniteNumber('HelloWorld'));
+        $this->assertFalse(Validator::IsFiniteNumber(true));
+        $this->assertFalse(Validator::IsFiniteNumber(false));
+        $this->assertFalse(Validator::IsFiniteNumber(null));
+        $this->assertFalse(Validator::IsFiniteNumber((object)[]));
+        $this->assertFalse(Validator::IsFiniteNumber([]));
+        $this->assertFalse(Validator::IsFiniteNumber(INF));
+        $this->assertFalse(Validator::IsFiniteNumber(-INF));
+        $this->assertFalse(Validator::IsFiniteNumber(NAN));
+        $this->assertFalse(Validator::IsFiniteNumber(pow(2,53) + 1));
+        $this->assertFalse(Validator::IsFiniteNumber(-pow(2,53) - 1));
+        $this->assertFalse(Validator::IsFiniteNumber(pow(2,53) + 2.0));
+        $this->assertFalse(Validator::IsFiniteNumber(-pow(2,53) - 2.0));
+    }
+
+    public function testIsFiniteNumberWithValidValues()
+    {
+        $this->assertTrue(Validator::IsFiniteNumber(0));
+        $this->assertTrue(Validator::IsFiniteNumber(5));
+        $this->assertTrue(Validator::IsFiniteNumber(5.5));
+        // float pow(2,53) + 1.0 evaluates to float pow(2,53)
+        $this->assertTrue(Validator::IsFiniteNumber(pow(2,53) + 1.0));
+        $this->assertTrue(Validator::IsFiniteNumber(-pow(2,53) - 1.0));
+        $this->assertTrue(Validator::IsFiniteNumber(pow(2,53)));
+    }
+
     public function testAreEventTagsValidValidEventTags()
     {
         // Empty attributes