diff --git a/source/build/src/timer.cpp b/source/build/src/timer.cpp
index 4463e91da..eade9fb3c 100644
--- a/source/build/src/timer.cpp
+++ b/source/build/src/timer.cpp
@@ -9,13 +9,15 @@
 using namespace std;
 using namespace chrono;
 
+EDUKE32_STATIC_ASSERT((steady_clock::period::den/steady_clock::period::num) >= 1000000000);
+
 static time_point<steady_clock> timerlastsample;
 static int timerticspersec;
 static void(*usertimercallback)(void) = NULL;
 
 int      timerGetRate(void)     { return timerticspersec; }
 uint32_t timerGetTicks(void)    { return duration_cast<milliseconds>(steady_clock::now().time_since_epoch()).count(); }
-uint64_t timerGetTicksU64(void) { return steady_clock::now().time_since_epoch().count(); }
+uint64_t timerGetTicksU64(void) { return steady_clock::now().time_since_epoch().count() * steady_clock::period::num; }
 uint64_t timerGetFreqU64(void)  { return steady_clock::period::den; }
 
 // Returns the time since an unspecified starting time in milliseconds.
@@ -35,12 +37,13 @@ int timerInit(int const tickspersecond)
 ATTRIBUTE((flatten)) void timerUpdate(void)
 {
     auto time = steady_clock::now();
-    int n = (time - timerlastsample).count() * (double)timerticspersec / timerGetFreqU64();
+    auto elapsedTime = time - timerlastsample;
+    int n = elapsedTime.count() * ((double)timerticspersec / timerGetFreqU64()) * steady_clock::period::num;
 
     if (n <= 0) return;
 
     totalclock += n;
-    timerlastsample = time;
+    timerlastsample += n*nanoseconds(1000000000/timerticspersec);
 
     if (usertimercallback)
         for (; n > 0; n--) usertimercallback();