diff --git a/rest_framework_json_api/filters.py b/rest_framework_json_api/filters.py
index f0b95a35..d1913d39 100644
--- a/rest_framework_json_api/filters.py
+++ b/rest_framework_json_api/filters.py
@@ -69,8 +69,8 @@ class QueryParameterValidationFilter(BaseFilterBackend):
     the rules at http://jsonapi.org/format/#query-parameters.
     """
     #: compiled regex that matches the allowed http://jsonapi.org/format/#query-parameters:
-    #: `sort` and `include` stand alone; `filter`, `fields`, and `page` have []'s
-    query_regex = re.compile(r'^(sort|include)$|^(filter|fields|page)(\[[\w\.\-]+\])?$')
+    #: `sort`, `include` and `format` stand alone; `filter`, `fields`, and `page` have []'s
+    query_regex = re.compile(r'^(sort|include|format)$|^(filter|fields|page)(\[[\w\.\-]+\])?$')
 
     def validate_query_params(self, request):
         """