This post will briefly show you how to retime runs to the exact millisecond, which is very useful for categories that are incredibly short where the difference between runs can come down to tenths or even hundreths of a second.

Somewes Frame Count

You can go to https://somewes.com/frame-count/ and just paste in the video link, set the frames per second, and then click through the frames until you find the start frame. Click the "Go" button next to the Start Frame text box to set the start frame, and repeat with the end frame. Afterwards, the final time can be found in the "Video Time" box. Important: it is NOT the time in the "Console Time" box. I find this one the most useful since it can be used on mobile and supports a wide variety of video hosting sites.

Mango Man's Retimer

If the video is on YouTube, you can alternatively go to https://retime.mcbe.wtf/ to retime. First, determine the video's frames per second by right clicking on the video and selecting the "Stats for nerds" option. The FPS is displayed after the @ in the "Current / Optimal Res" line. Next, find the start frame of the video by using the . and , keys to advance forward/backward one frame. Then, right click on the video and select the "Copy debug info" option, and paste your clipboard into the "Starting frame" textbook on the retime page. Rinse and repeat for the ending frame, and you should have your frame-counted time displayed in the "Time" text box. It even auto-generates a mod note for you!