Here's what I do (you can check my log for it). Instead of using calculators to determine how many calories I burn generally over the course of the day, I ONLY do that for my BMR. So I calculate my BMR (~2,000cal) and then I calculate the separate activities by looking them up... not by using a calculator for "light activity for 2hrs."
Example from my log:
-= Calorie Log =-
FOOD / ACTIVITY CALORIES
2 slices of pizza +540
5 eggs +310
4 cups whole milk +600
2 scoops protein +240
Chicken platter +850
1 serving grapes +60
Total in +2,600
BMR -2,000
Walked 8 miles -800
Worked out -200
Thermic effect of food -300
Total out -3,300
Balance -700cal
After cutting for 6 weeks at -500cal a day and only losing 4lbs (instead of the predicted 6), I simply am now cutting at -700cal.
There is some estimating/rounding involved (like with how many calories I've burned lifting or walking, but I look those up for ballpark figures), so I just adjust the caloric balance for the day and continue for there.
Even if my numbers are way off, as long as I drop weight consistently and at the right pace it doesn't matter to me because I've found a balance. Kind of like how you use an old scale, and you're not sure if its 5lbs heavy or 5lbs light, but as long as its consistent and you go from 230lbs to 220lbs, you know you've dropped 10lbs.