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Useless yet interesting Calculations

189,514 subscribers a community for 3 years, 11 months

last post today [+]

Submission Rules

  1. Proper title tags are required for all posts or it will be removed! The tags accepted are at the end of the sidebar down there.

  2. State clearly what is being or what you want calculated in the title. [Request] posts must have a calculable answer; otherwise, they will be removed.

  3. Give credit where credit is due—include the user who made the calculations in any post you submit: ex. "[RDTM] /u/FragTheWhale calculates...".

  4. For easy and quick math results (ex. How many feet are in a mile?) use Wolfram|Alpha™. Posts containing "simple math" will be removed, as well as requests whose answers are easily searchable online, and any other post at the moderators' discretion. For more abstract math, try /r/math or /r/learnmath.

  5. Posts which seem to be asking for help on homework will be removed. Try /r/homeworkhelp or /r/cheatatmathhomework instead.

Comment Rules

  1. This subreddit has a zero-tolerance policy for hateful or unnecessary language. There is no warning for hate speech of any kind. Rule breaking posts/comments will have a temporary ban that will serve as a first offense "warning". Repeat or egregious offenders will be banned permanently. Reddit's site-wide rules still apply here. Also, don't be a dick.

  2. Do not submit top-level comments in [Request] posts that are not an attempt at an answer or a request for clarification. Jokes or off-topic top-level comments will be removed.

  3. When answering [Request] posts, please cite reputable sources to defend any evidence that cannot be proven using your own math.

Report any spam/rule breaking posts to the mods with the report button. Be sure to include the reason for your report!

Request Point System!

The bot is currently down.

Want to thank someone for answering your request post? Give them a request point! Reply to someone in your [Request] thread with a checkmark (see below) and a few nice words and /u/TDTMBot will oblige!

Want to earn RP? Answer requests! Earn points and cool flair!


View RP Rules and guidelines here.

See your own history at /r/theydidthemath/w/user/YourUsernameHere

Or, check out the monthly scoreboard! The top point earner of the month gets a special golden username!

LaTeX and subscripts/superscripts

[; e^{\pi i} + 1 = 0 ;]

Superscripts and subscripts are supported in this subreddit, and LaTeX is used here as well. If the above equation looks like garbled code, or for information on how to display subscripts and superscripts, check our wiki page.

Our Friends & Partner Subreddits:

  • /r/theydidthemonstermath
  • /r/itwasagraveyardgraph
  • /r/theydidtheexperiment
  • /r/SmarterEveryDay
  • /r/EverythingScience
  • /r/shittytheydidthemath
  • /r/theydidtheresearch
  • /r/inspirationscience
  • /r/InAWorld


We require title tags. Here are the tags we accept and what they are for. Please keep them at the start of your post.

  • [Request] - Asking the /r/theydidthemath community to do the math for you!

  • [Self] - You did the math and want to share it!

  • [RDTM] - "Reddit Did The Math", linking to a comment or post on Reddit where someone else does the math!

  • [Off-Site] - Use when linking to any site, including Imgur, that is not

  • [Meta] - Non-math posts regarding the subreddit itself. Don't use this unless you really have to.

^Sidebar ^image ^from ^Randall ^Monroe's ^xkcd

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