diff --git a/grbl.cpp b/grbl.cpp
index c5ef1f6..1d9376b 100644
--- a/grbl.cpp
+++ b/grbl.cpp
@@ -36,7 +36,7 @@ grbl::program::program(std::string filename) {
 }
 
 static auto comment_re = std::regex(R"(\(([^)]*)\))");
-static auto gcode_re = std::regex(R"(([a-zA-Z0-9\s.\-]+)\s*(\(([^)]*)\))?)");
+static auto gcode_re = std::regex(R"(([a-zA-Z0-9\s.\-]+)\s*(;.*|\(([^)]*)\))?)");
 
 bool grbl::program::load_from_stream(std::istream& in) {
     instructions.clear();
diff --git a/grbl_test.cpp b/grbl_test.cpp
index 57dd300..f921568 100644
--- a/grbl_test.cpp
+++ b/grbl_test.cpp
@@ -19,7 +19,7 @@ TEST(grbl_program, load_from_string) {
 
 G94 ( Millimeters per minute feed rate. )
 G21 ( Units == Millimeters. )
-F600.00000
+F600.00000 ; another type of comment
 X3.87739 Y78.52820
 )";
     pgm.load_from_string(content);
diff --git a/program.nc b/program.nc
index 4ce4449..42d5628 100644
--- a/program.nc
+++ b/program.nc
@@ -4,7 +4,7 @@
 G94 ( Millimeters per minute feed rate. )
 G21 ( Units == Millimeters. )
 G90 ( Absolute coordinates. )
-S10000 ( RPM spindle speed. )
+S20000 ( RPM spindle speed. )
 
 M3 S24000
 G4 P3