Everyone is different as far as what temperature makes them the most comfortable.
Comfort with temperature also differs with indoor and outdoor temperatures.
For example, someone may be comfortable with 85 degrees outside, but would be super uncomfortable with the same temperature inside. I asked some friends to see what temperature makes them turn their air conditioners on in the summer. The first friend I asked is Paul. Paul lives in the south, where it is notoriously hot and humid, even before the summer months. Paul said that as soon as it hits 75 degrees, his central air is turned on in his home. He explained that it is more the humidity than the heat that motivates him to turn on his A/C. Paul does not want his house getting that humid, moldy, uncomfortable feeling. He runs his central air until it cools down in the winter which does not always happen where he lives. I asked my friend Eri, who lives up north. Eri does not have central air conditioning, because it is not necessary where she lives. Instead, she has two window air conditioner units- one in her bedroom and one in the living room. Eri said that she will usually turn on her window A/C units when it gets up to 85 degrees or when it feels humid. It is possible for her to get comfort most of the summer from windows being open and using a fan, instead of spending money on air conditioning. It is really interesting how in different parts of the country, people have different opinions on when they feel it is necessary to use their air conditioning.