Every college tells you to "maintain 75% attendance," but very few actually explain how that number is worked out. The formula itself is simple:
Attendance % = (Classes Attended ÷ Total Classes Held) × 100
Let's put that into a real example. Say your semester has had 120 classes so far, and you have attended 93 of them. Your current attendance stands at:
93 ÷ 120 × 100 = 77.5%
That is comfortably above the usual 75% cutoff most colleges enforce, but the number changes every single day a new class is held — whether you attend it or not. This is the part students usually get wrong: skipping a class doesn't just fail to add a "present," it also increases the total denominator, which quietly drags your percentage down faster than most people expect.
Here is the mistake in action. If you skip the next 5 classes in a row, your total becomes 125 and your attended count stays at 93:
93 ÷ 125 × 100 = 74.4%
One short stretch of skipped classes is enough to drop you below the minimum. That is exactly why a static "I'm fine for now" mental calculation breaks down over a semester — the total keeps growing whether you show up or not.
Instead of doing this math by hand every week, plug your attended and total class counts into our Bunk Calculator and it will instantly tell you how many classes you can safely miss, or how many you now need to attend, to stay above your college's required percentage.