When I check the page loading time for a page in chrome Dev tool under network tab the system has taken 6 seconds

When I check the page loading time for a page in chrome Dev tool under performance tab the system has taken 8 seconds

When I check using jmeter by using blaze meter recorded file its taking 12 seconds..
Note: I have one main jsp request and 5 sub request....

* Number of User:1
* Ramp-up period:1
* Loop count:1