In case anyone is wondering how to time these to the millisecond without having to learn video editing, watch your video at a slower speed and time it how you would normally. Once you have your total [slowed] time, just multiply it by the speed you watched at.

If you watched at 0.25x speed, and you timed 277.68 seconds, then 277.68 * 0.25 = 69.420 seconds.

If you wanna go the extra mile, watch as slow as your media player will allow (for example, mine goes down to 0.03x speed), repeat the process 2 or 3 more times, then average your results to account for human error :)