Request for here, using this video, and the Watch Frame By Frame tool.
- Rocket is Launched at 00:08:77 and trip ends at 0:13:57. 4.8 seconds.
- Doomguy starts running at 00:09:40 and stops to turn around at 00:12:00. 2.6 seconds.
- Rocket Launcher is 300 m/s; 300 m/s * 4.8s = 1440 meters.
- 1440m / 2.6s = 553.846153846 m/s or Mach 1.614711818793003.
- That's Supersonic movement speed and combat speed is likely higher.
- Also note that, Doomguy's speed doesn't quite count his build up speed or the part where he breaks at the end; meaning his top speed is likely even higher as well.
Note: A lot of people appear confused about this feat. But I have addressed it multiple times. It's not a glitch, it's a literal technique similarly common like Sonic's figure 8 technique or Mario and Samus's Wall jumping. He does use the walls to build up momentum, but he's still in full control while running and still physically outpaces the rockets via his own physical speed. So this definitely scales to his movement and combat speed. This isn't even a "Game breaker" or anything even close to that. It's a basic technique that he does naturally.
He also still runs faster than RPGs without strife running or wall running; plus he has consistent feats such as dodging machine generated electricity.
Conclusion[]
Doomguy is universally Supersonic or above