What exactly measures pageSize?



Could somebody explain me, what exactly measures pageSize?

Taking the url http://seotoolsforexcel.com/pagesize/ i get the pageSize as 17167. But looking into developer tools i see something absolutely other:

  • the whole site with assets is 548 kB
  • only html file is 4,9 kB
  • content length of html file is correspondingly 4,7 kB

If i crawl the url with Screaming Frog the size is 17167 too... BUT reading documentation of Screaming Frog, the size would be

Size is in bytes, divide by 1024 to convert to kilobytes. The value is set from the Content-Length header if provided, if not it’s set to zero. For HTML pages this is updated to the size of the (uncompressed) HTML in bytes....

It is an absolute misterium for me: where are 17167 coming from and what means this number?
Screenshot attached



I'm not 100% sure but I believe it is the size of all html code. If you copy the html and save it as .txt, the file size matches the Seotools results.

Reviewing the code of the function, it seems to calculate the length of the encoded body string.


Yes, it matches. But what means in this case the size of the file displayed in the developer tool and its Content Length?


Not sure, anyone else?