diff --git a/include/olm/base64.hh b/include/olm/base64.hh
index 0a7435b9b0cf874b153d778d8d01d2075b225a95..a68894d7f7a160a4cd0f058bf4f08f8d5710232b 100644
--- a/include/olm/base64.hh
+++ b/include/olm/base64.hh
@@ -12,8 +12,8 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-#ifndef AXOLOLT_BASE64_HH_
-#define AXOLOLT_BASE64_HH_
+#ifndef OLM_BASE64_HH_
+#define OLM_BASE64_HH_
 
 #include <cstddef>
 #include <cstdint>
@@ -46,4 +46,4 @@ void decode_base64(
 } // namespace olm
 
 
-#endif /* AXOLOLT_BASE64_HH_ */
+#endif /* OLM_BASE64_HH_ */