Django Toolbar gives different times when same template is loaded

Django Toolbar gives different times when same template is loaded

When using the Django debug toolbar, it says a page might load in say 4000
ms. But when we reload the page (with ctrl+F5 to clear the cache) it says
it loads in say 4400 ms -- or 3600 ms. Is there a more accurate way to
benchmark the load time? The reason is that we want to optimize page load
times and want to make sure that we can see cause and effect clearly.