diff --git a/src/common/rendering/v_video.h b/src/common/rendering/v_video.h
index 1ffbfea090..0f94d7fc8c 100644
--- a/src/common/rendering/v_video.h
+++ b/src/common/rendering/v_video.h
@@ -276,8 +276,8 @@ public:
 	static float GetZNear() { return 5.f; }
 	static float GetZFar() { return 65536.f; }
 
-	// The original size of the framebuffer as selected in the video menu.
 	uint64_t FrameTime = 0;
+	uint64_t FrameTimeNS = 0;
 
 private:
 	uint64_t fpsLimitTime = 0;
diff --git a/src/common/startscreen/startscreen.cpp b/src/common/startscreen/startscreen.cpp
index 660561fd23..2d682f0c04 100644
--- a/src/common/startscreen/startscreen.cpp
+++ b/src/common/startscreen/startscreen.cpp
@@ -659,6 +659,7 @@ void FStartScreen::Render(bool force)
 	if (nowtime - screen->FrameTime > 30 || force)
 	{
 		screen->FrameTime = nowtime;
+		screen->FrameTimeNS = I_nsTime();
 		screen->BeginFrame();
 		twod->ClearClipRect();
 		I_GetEvent();
diff --git a/src/d_main.cpp b/src/d_main.cpp
index 4d4535acaa..b1119efb5c 100644
--- a/src/d_main.cpp
+++ b/src/d_main.cpp
@@ -773,33 +773,45 @@ static void DrawPaletteTester(int paletteno)
 // Draws the fps counter, dot ticker, and palette debug.
 //
 //==========================================================================
-uint64_t LastFPS, LastMSCount;
+uint64_t LastFPS, LastAvgNSCount, LastMaxNSCount, LastMinNSCount;
 
 void CalcFps()
 {
-	static uint64_t LastMS = 0, LastSec = 0, FrameCount = 0, LastTic = 0;
+	static uint64_t LastNS = 0, LastStart = 0, FrameCount = 0, AccumNS = 0, MaxNS = 0, MinNS = 0xffff'ffff'ffffULL;
 
-	uint64_t ms = screen->FrameTime;
-	uint64_t howlong = ms - LastMS;
+	uint64_t ns = screen->FrameTimeNS;
+	uint64_t howlong = ns - LastNS;
 	if ((signed)howlong > 0) // do this only once per frame.
 	{
-		uint32_t thisSec = (uint32_t)(ms / 1000);
-		if (LastSec < thisSec)
-		{
-			LastFPS = FrameCount / (thisSec - LastSec);
-			LastSec = thisSec;
-			FrameCount = 0;
-		}
 		FrameCount++;
-		LastMS = ms;
-		LastMSCount = howlong;
+
+		// Wait until at least a second has elapsed
+		if (LastStart / 1'000'000'000ULL < ns / 1'000'000'000ULL)
+		{
+			LastFPS = (FrameCount * 1'000'000'000ULL + 100'000'000ULL) / (ns - LastStart);
+			LastStart = ns;
+			LastAvgNSCount = AccumNS / FrameCount;
+			LastMaxNSCount = MaxNS;
+			LastMinNSCount = MinNS;
+			FrameCount = 0;
+			AccumNS = 0;
+			MaxNS = 0;
+			MinNS = 0xffff'ffff'ffffULL;
+		}
+		LastNS = ns;
+		AccumNS += howlong;
+		MaxNS = std::max(MaxNS, howlong);
+		MinNS = std::min(MinNS, howlong);
 	}
 }
 
 ADD_STAT(fps)
 {
 	CalcFps();
-	return FStringf("%2llu ms (%3llu fps)", (unsigned long long)LastMSCount , (unsigned long long)LastFPS);
+	return FStringf("%2llu.%llu ms avg (%4llu fps), %2llu.%llu ms max, %2llu.%llu ms min",
+		(unsigned long long)(LastAvgNSCount / 1'000'000ULL), (unsigned long long)(LastAvgNSCount / 100'000ULL % 10), (unsigned long long)LastFPS,
+		(unsigned long long)(LastMaxNSCount / 1'000'000ULL), (unsigned long long)(LastMaxNSCount / 100'000ULL % 10),
+		(unsigned long long)(LastMinNSCount / 1'000'000ULL), (unsigned long long)(LastMinNSCount / 100'000ULL % 10));
 }
 
 static void DrawRateStuff()
@@ -815,7 +827,7 @@ static void DrawRateStuff()
 		int rate_x;
 		int textScale = active_con_scale(twod);
 
-		chars = mysnprintf(fpsbuff, countof(fpsbuff), "%2llu ms (%3llu fps)", (unsigned long long)LastMSCount, (unsigned long long)LastFPS);
+		chars = mysnprintf(fpsbuff, countof(fpsbuff), "%2llu.%llu ms (%4llu fps)", (unsigned long long)(LastAvgNSCount / 1'000'000ULL), (unsigned long long)(LastAvgNSCount / 100'000ULL % 10), (unsigned long long)LastFPS);
 		rate_x = screen->GetWidth() / textScale - NewConsoleFont->StringWidth(&fpsbuff[0]);
 		ClearRect(twod, rate_x * textScale, 0, screen->GetWidth(), NewConsoleFont->GetHeight() * textScale, GPalette.BlackIndex, 0);
 		DrawText(twod, NewConsoleFont, CR_WHITE, rate_x, 0, (char*)&fpsbuff[0],
@@ -977,6 +989,7 @@ void D_Display ()
 	}
 	
 	screen->FrameTime = I_msTimeFS();
+	screen->FrameTimeNS = I_nsTime();
 	TexAnim.UpdateAnimations(screen->FrameTime);
 	R_UpdateSky(screen->FrameTime);
 	screen->BeginFrame();