Help with Activity Level for working out Macros and BMR

Choosing my activity level for a Calculator to try and work out my calories. The calories seem to differ quite a bit when you change the level. So can anyone advise on what mine would be? I have a 9-5 desk sedatory job Mon-Fri. Here is my activity/fitness regime:

Mon - Teach a 1 hour class (cardio and strength)
Tue -
Wed - Strength training 45-55 min and 20 min HIIT
Thur - Teach a 1 hour class (cardio and strength)
Fri
Sat - Strength training 45-55 min and 20 min HIIT
Sun - Strength training 45-55 min and 20 min HIIT

I sometimes only have one day off a week, but I do switch it up a bit and usually train 5 times a week minimum