For calorie counters: How to factor in the TEF?

Hey guys, like I mentioned in past postings, I am pretty much the calorie-counting type of guy, when it comes to managing my weight. I am currently trying to gain some mass with strength training and a slight caloric surplus. All in all, I am not the most disciplined eater and I also drink a couple of beers with my friends once or twice a month. Taking this into account, I got the feeling that I should have gained more weight - not just muscle, but also a little more fat - than I actually did. I thought about this mystery alot recently and I came to the conclusion that I must have missed a relevant factor in my calculation. And after some research, I think, it is probably the TEF (thermic effect of food), which describes the amount of energy the body expends to digest the food you eat. From what I found out, it's round about 10% of the number of calories you eat, probably higher for a protein-rich nutrition. This number I never included into my calculation. This also fits my wife's experience, since she lost weight a fair bit quicker than planned.

So to those calorie counter pros among you: How do you handle the TEF? Do you just take 10% of your calories-in and add it on top of your calories-out? And do you know, if TDEE-calculators already include the TEF? I guess rather not, since these calculators don't ask about your specific nutrition at all, right?

Edited