diff --git a/vowpalwabbit/fb_parser/tests/flatbuffer_parser_test.cc b/vowpalwabbit/fb_parser/tests/flatbuffer_parser_test.cc
index 5692b96b022..03be8bbce13 100644
--- a/vowpalwabbit/fb_parser/tests/flatbuffer_parser_test.cc
+++ b/vowpalwabbit/fb_parser/tests/flatbuffer_parser_test.cc
@@ -65,7 +65,6 @@ TEST(flatbuffer_parser_tests, test_flatbuffer_standalone_example)
   builder.FinishSizePrefixed(root);
 
   uint8_t* buf = builder.GetBufferPointer();
-  int size = builder.GetSize();
 
   VW::multi_ex examples;
   examples.push_back(&VW::get_unused_example(all));
@@ -109,7 +108,6 @@ TEST(flatbuffer_parser_tests, test_flatbuffer_collection)
   builder.FinishSizePrefixed(root);
 
   uint8_t* buf = builder.GetBufferPointer();
-  int size = builder.GetSize();
 
   VW::multi_ex examples;
   examples.push_back(&VW::get_unused_example(all));