I Did The Math
Usually seen on online forums or other forms of digital media. Likely a follow-up to something peculiar, such as the speed at which a character in a video game travels, swims, sprints, etc.

Internet Slang commonly used on Reddit, especially subreddits like r/theydidthemath, where one might try to explain some abstract concept using reason, science and/or math.
A whale died with 64 lbs of plastic in its stomach. IDTM to put it in perspective.
IDTM: How much is a pot of gold at the end of a rainbow worth?
by Leks Starkan November 19, 2018
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