diff --git a/grbl/gcode.h b/grbl/gcode.h
index 16a7ec8b..ee240283 100644
--- a/grbl/gcode.h
+++ b/grbl/gcode.h
@@ -202,7 +202,7 @@ typedef struct {
 
 typedef struct {
   float f;         // Feed
-  float ijk[3];    // I,J,K Axis arc offsets
+  float ijk[N_AXIS];    // I,J,K Axis arc offsets
   uint8_t l;       // G10 or canned cycles parameters
   int32_t n;       // Line number
   float p;         // G10 or dwell parameters