diff --git a/src/gui/Timer.h b/src/gui/Timer.h
index f4886a0..376efd7 100644
--- a/src/gui/Timer.h
+++ b/src/gui/Timer.h
@@ -3,16 +3,16 @@
 
 class Timer {
 public:
-    Timer() { clock_gettime(CLOCK_REALTIME, &beg_); }
+    Timer() { clock_gettime(CLOCK_MONOTONIC, &beg_); }
 
     double elapsed() {
-        clock_gettime(CLOCK_REALTIME, &end_);
+        clock_gettime(CLOCK_MONOTONIC, &end_);
         return end_.tv_sec - beg_.tv_sec +
                (end_.tv_nsec - beg_.tv_nsec) / 1000000000.;
     }
 
-    void reset() { clock_gettime(CLOCK_REALTIME, &beg_); }
+    void reset() { clock_gettime(CLOCK_MONOTONIC, &beg_); }
 
 private:
     timespec beg_, end_;
-};
\ No newline at end of file
+};