A simple way to get cost per mb is to test http://1mb.website/ and use https://whatdoesmysitecost.com/ .

Lets if I can find a good example.

Haha, that didn't work out ok:

Lets try to use this and see what we can get out of it: https://whatdoesmysitecost.com/test/160909_QB_NZW#gniCost

Got a simple version coming with an example of showing percentage of daily gross national income per capita in Madagascar (we can change country or have a couple of them).

I'm not 100% comfortable with:

• The calculation of the cost should be 100% open. It comes from whatdoesmysitecost.com (the original figures comes from ITU and the World Bank) and the site is not Open Source (the data is free and it's built on top of (or using) WebPageTest) and that's annoys me because it's no way to check the actual numbers.

• Is it a too complicated metric of percentage of daily gross national income per capital? I mean the metric is good and something really important but I don't like that's complicated to even know if the numbers are correct.

• The cost is for the site on desktop. For mobile it depends on lazy loading (but that's kind of ok I think) the main thing is srcset so the actual numbers will not match. We are saying one cost it will not be the same on mobile.

For the first one: We could ask Tim Kadlec to Open Source the code so people see how it's calculated (the raw numbers)? I've emailed him before about mobile proxies but never got an answer but I can try again.

Change 309960 had a related patch set uploaded (by Phedenskog):
Show the cost for images.

https://gerrit.wikimedia.org/r/309960

Thanks @ori : The numbers are from this report: http://www.itu.int/en/ITU-D/Statistics/Documents/statistics/2016/WTID_2016_ListOfIndicators.pdf and correlated with income in different countries from http://data.worldbank.org/

Potentially put this data on to a wiki page in order to make use of it.

Good question from @Peter : What do we want the user to do with this information, if we expose it through Performance Inspector?

I think we are hoping that this will help people 1 - collect data about how heavy certain popular pages are/all pages which belong to a wikiproject or "bundle" kind of thing, and 2 - start thinking about how to optimise the readers' experience based on that?

For Wikimedia examples, I tried a few pages. Most were very encouragingly small, but I did find one large page on Commons. If you have better examples, especially of Wikipedia mainspace articles, add them here. :-)

• https://en.wikipedia.org/wiki/Moon weighs 0.3MB
  • https://whatdoesmysitecost.com/test/180424_0C_426a2d284f3854dd22a9d4e51fc08646
• https://commons.wikimedia.org/wiki/Commons:Picture_of_the_day weighs 0.29MB
  • https://whatdoesmysitecost.com/test/180424_K2_caf112d2e55845c75ea06148fb123c61
• https://commons.wikimedia.org/wiki/Commons:Featured_pictures/Astronomy weighs 7.41MB
  • https://whatdoesmysitecost.com/test/180424_KE_71b87f337ed5ce06ac21df7cf10fdfb3

Change 309960 abandoned by Phedenskog:
Show the cost for images.

Reason:
We decided not to work on the Performance Inspector.

https://gerrit.wikimedia.org/r/309960