Attendance Calculator
Check your attendance percentage and find out exactly how many consecutive classes you must attend to reach the required threshold — or how many you can still safely skip.
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Save ⟶How to use the Attendance Calculator
- 1Enter classes attended in the form on the left.
- 2Fill in the remaining fields — the result updates automatically as you type.
- 3Review the highlighted result and the supporting breakdown on the right.
- 4Use Copy, Share or Print to save or send your result.
The attendance recovery formula
If you must reach a fraction r of attendance, and you've attended a out of t classes, the number of consecutive classes x you need satisfies (a + x)/(t + x) ≥ r, giving x ≥ (rt − a)/(1 − r). Notice the denominator: the closer the requirement is to 100%, the brutally faster the needed classes grow.
Conversely, when you're above the threshold, you can skip at most a/r − t upcoming classes before dipping below it. Recovering attendance is always slower than losing it — each skipped class needs roughly r/(1−r) attended classes to offset at threshold r (three classes per skip at 75%).
Frequently Asked Questions
▸How is attendance percentage calculated?
Classes attended divided by total classes held, times 100. 68 of 90 classes = 75.6%.
▸Why does recovering attendance take so long?
Every class you attend also increases the total. At a 75% requirement, each missed class takes three attended classes to neutralize.