diff --git a/source/include/math_helper.h b/source/include/math_helper.h
index 65098b3..cbc4d66 100644
--- a/source/include/math_helper.h
+++ b/source/include/math_helper.h
@@ -10,7 +10,11 @@
 #ifndef DORAYME_MATH_HELPER_H
 #define DORAYME_MATH_HELPER_H
 
+#include <math.h>
+
 void set_equal_precision(double v);
 bool double_equal(double a, double b);
 
+double deg_to_rad(double deg);
+
 #endif //DORAYME_MATH_HELPER_H
diff --git a/source/math_helper.cpp b/source/math_helper.cpp
index 4ce2a0b..478e305 100644
--- a/source/math_helper.cpp
+++ b/source/math_helper.cpp
@@ -22,3 +22,8 @@ bool double_equal(double a, double b)
 {
     return fabs(a - b) < current_precision;
 }
+
+double deg_to_rad(double deg)
+{
+   return deg * M_PI / 180.;
+}
\ No newline at end of file