diff --git a/source/obs/gs/gs-effect.cpp b/source/obs/gs/gs-effect.cpp
index 03915e39..6b11fdf4 100644
--- a/source/obs/gs/gs-effect.cpp
+++ b/source/obs/gs/gs-effect.cpp
@@ -726,7 +726,7 @@ void gs::effect_parameter::get_string(std::string& v)
 	size_t   ptr_len = gs_effect_get_val_size(_param);
 	uint8_t* ptr     = static_cast<uint8_t*>(gs_effect_get_val(_param));
 	if (ptr) {
-		v = std::string(ptr, ptr + ptr_len);
+		v = std::string(ptr, ptr + ptr_len - 1);
 		bfree(ptr);
 	} else {
 		v = "";
@@ -740,7 +740,7 @@ void gs::effect_parameter::get_default_string(std::string& v)
 	size_t   ptr_len = gs_effect_get_default_val_size(_param);
 	uint8_t* ptr     = static_cast<uint8_t*>(gs_effect_get_default_val(_param));
 	if (ptr) {
-		v = std::string(ptr, ptr + ptr_len);
+		v = std::string(ptr, ptr + ptr_len - 1);
 		bfree(ptr);
 	} else {
 		v = "";