diff --git a/src/engine/engine_vis_visualize.c b/src/engine/engine_vis_visualize.c
index 9154fa4d..393bd509 100644
--- a/src/engine/engine_vis_visualize.c
+++ b/src/engine/engine_vis_visualize.c
@@ -62,7 +62,7 @@ static void makeLabel(const mjModel* m, mjtObj type, int id, char* label) {
   }
 
   // copy result into label
-  strncpy(label, txt, 99);
+  strncpy(label, txt, 100);
   label[99] = '\0';
 }