diff --git a/src/mesh/http/ContentHelper.h b/src/mesh/http/ContentHelper.h
index a80c39f47..e5d3a2f57 100644
--- a/src/mesh/http/ContentHelper.h
+++ b/src/mesh/http/ContentHelper.h
@@ -1,5 +1,6 @@
 #include <Arduino.h>
 #include <functional>
+#include <string>
 
 #define BoolToString(x) ((x) ? "true" : "false")