diff --git a/include/sofort/sofort.h b/include/sofort/sofort.h
index a8373a1..abf80e2 100644
--- a/include/sofort/sofort.h
+++ b/include/sofort/sofort.h
@@ -1,5 +1,5 @@
-#ifndef SFRT_H
-#define SFRT_H
+#ifndef SOFORT_H
+#define SOFORT_H
 
 #include <stdint.h>
 #include <stdio.h>
diff --git a/include/sofort/sofort_api.h b/include/sofort/sofort_api.h
index 5f0b2d9..26659fd 100644
--- a/include/sofort/sofort_api.h
+++ b/include/sofort/sofort_api.h
@@ -1,5 +1,5 @@
-#ifndef SFRT_API_H
-#define SFRT_API_H
+#ifndef SOFORT_API_H
+#define SOFORT_API_H
 
 #include <limits.h>
 
diff --git a/src/internal/sofort_driver_impl.h b/src/internal/sofort_driver_impl.h
index b901629..d9aa364 100644
--- a/src/internal/sofort_driver_impl.h
+++ b/src/internal/sofort_driver_impl.h
@@ -1,5 +1,5 @@
-#ifndef SFRT_DRIVER_IMPL_H
-#define SFRT_DRIVER_IMPL_H
+#ifndef SOFORT_DRIVER_IMPL_H
+#define SOFORT_DRIVER_IMPL_H
 
 #include <stdint.h>
 #include <stdio.h>