How attendance percentage is calculated (with examples)
Attendance percentage looks simple, and it mostly is. But a few details about what gets counted decide whether your number matches the one your college has.
The formula
Attendance % = classes attended ÷ classes held × 100
If 40 classes have been held this semester and you were present for 33, your attendance is 33 ÷ 40 × 100 = 82.5%.
That's it. Everything else is about which classes go into each number.
What counts as a class "held"
A class is held when it actually happened: a teacher took the period and attendance was recorded, whether or not you were there. So these usually count as held:
- Every regular period on your timetable that took place.
- Periods you missed, for any reason. A missed class still counts in the "held" total; it just doesn't count in "attended".
- Extra or makeup classes, if attendance was taken.
And these usually don't count as held:
- Public holidays and college holidays.
- Classes the teacher cancelled.
- Periods with no teacher where no attendance was taken.
Things like library periods, events and sports slots vary between colleges, so check how yours handles them. More on holidays and cancelled classes.
Periods, not days
Most colleges count attendance per period, not per day. If you have three periods on Monday and you leave after the first, that's 1 attended out of 3 held, not a full day present or a full day absent. Counting days instead of periods is the single most common reason a personal estimate is off.
A worked example
Say a subject meets 4 times a week and you're five weeks in:
| Week | Held | Attended | Running % |
|---|---|---|---|
| 1 | 4 | 4 | 100% |
| 2 | 3 (one cancelled) | 2 | 6 of 7 = 85.7% |
| 3 | 4 | 3 | 9 of 11 = 81.8% |
| 4 | 4 | 4 | 13 of 15 = 86.7% |
| 5 | 4 | 2 | 15 of 19 = 78.9% |
Notice that the cancelled class in week 2 just disappears from both columns. It doesn't help you or hurt you.
Why your number might differ from the register
- You counted days instead of periods. See above.
- You forgot a class was held. An extra Saturday class or a rescheduled period is easy to miss when counting from memory.
- You were marked absent by mistake. It happens, especially if you came in late or the teacher read the list quickly. If you keep your own record, you can spot this early. See how to fix an attendance mistake.
- Different cut-off dates. The college may calculate up to a certain date, while you're counting up to today.
Rounding
74.6% is not 75%. Some colleges round, many don't, and you don't want to find out which at the end of the semester. Treat your target as a floor and aim to stay a little above it.