how to check the data downloaded when i open my website
I was looking for a tool which give me the size of downloaded data when i open some website 
like when i open Gmail.com , it says 



                         downloaded data : 2.012.544 bytes
how to check the data downloaded when i open my website
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I was looking for a tool which give me the size of downloaded data when i open some website 
like when i open Gmail.com , it says 



                         downloaded data : 2.012.544 bytes