How do i know how many calories I'm burning from a certain exercise?

[Burning_Inside]

How is it possible to find exactly how many calories you're burning? For instance, how would I know how many cals im burning from doing 20 minutes of sprint intervals, as compared to 20 minutes of straight jogging?

How do i find out how many I burn by doing a lifting routine?

 

[MS]

Total room calorimetry is the only way to know. And even then you would find that how much you burn in a session changes from day to day.

 

[Burning_Inside]

So is there any way at all to even generalize?
I feel like I need to know exactly how much i'm melting of so i know exactly how much to eat to keep a steady fat burning going on and not over eat or under eat...