diff --git a/src/convert_json.cpp b/src/convert_json.cpp
index e03508e21fe2d0a77a76013d3f3a79a3168c9a0c..e548c45f54ea61a697844b883f53e595832d281f 100644
--- a/src/convert_json.cpp
+++ b/src/convert_json.cpp
@@ -52,7 +52,13 @@ Json::Value fetchJsonValue(const std::string &url,
 	if (!reader.parse(stream, root)) {
 		errorstream << "URL: " << url << std::endl;
 		errorstream << "Failed to parse json data " << reader.getFormattedErrorMessages();
-		errorstream << "data: \"" << fetch_result.data << "\"" << std::endl;
+		if (fetch_result.data.size() > 100) {
+			errorstream << "Data (" << fetch_result.data.size()
+				<< " bytes) printed to warningstream." << std::endl;
+			warningstream << "data: \"" << fetch_result.data << "\"" << std::endl;
+		} else {
+			errorstream << "data: \"" << fetch_result.data << "\"" << std::endl;
+		}
 		return Json::Value();
 	}
 
diff --git a/src/script/lua_api/l_util.cpp b/src/script/lua_api/l_util.cpp
index 3f7e15acfa79e5fd3cf9bd1934094fce41b00929..39863b987a7dea893847519e727fcd864f19b463 100644
--- a/src/script/lua_api/l_util.cpp
+++ b/src/script/lua_api/l_util.cpp
@@ -161,8 +161,14 @@ int ModApiUtil::l_parse_json(lua_State *L)
 		if (!reader.parse(stream, root)) {
 			errorstream << "Failed to parse json data "
 				<< reader.getFormattedErrorMessages();
-			errorstream << "data: \"" << jsonstr << "\""
-				<< std::endl;
+			size_t jlen = strlen(jsonstr);
+			if (jlen > 100) {
+				errorstream << "Data (" << jlen
+					<< " bytes) printed to warningstream." << std::endl;
+				warningstream << "data: \"" << jsonstr << "\"" << std::endl;
+			} else {
+				errorstream << "data: \"" << jsonstr << "\"" << std::endl;
+			}
 			lua_pushnil(L);
 			return 1;
 		}