Attendance calculator
How many classes can I skip?
Enter how many classes have been held and how many you attended. It tells you your percentage, how many you can still miss and stay above your college's requirement, or how many you need to attend in a row to get back.
Your attendance
83.3%
You can skip 16 more classes and stay at or above 75%.
Skip 16 and you'll be at 75.3% — 125 of 166.
How it works it out
Above the line
Classes you can skip = attended ÷ required − held, rounded down. Skipping adds a class held and no class attended, so this is the most you can add before the percentage falls below the requirement.
Below the line
Classes to attend = (required × held − attended) ÷ (1 − required), rounded up. Every class you attend adds one to both sides, so recovering takes longer than falling behind did.
Questions students ask
How is attendance percentage calculated?
Classes attended divided by classes held, times 100. 125 attended out of 150 held is 83.3%. Classes that were cancelled or not held do not count on either side.
How many classes can I miss and still have 75% attendance?
Divide the classes you have attended by 0.75, then subtract the classes held so far, and round down. With 125 attended out of 150 held: 125 ÷ 0.75 = 166.7, minus 150 is 16.7, so you can skip 16 more and still be at 75.3%. Skip 17 and you drop to 74.9%.
I'm below 75%. How many classes do I need to attend to get back?
Take 75% of the classes held, subtract what you have attended, and divide by 0.25, rounding up. With 40 attended out of 60 held: 0.75 × 60 = 45, 45 − 40 = 5, and 5 ÷ 0.25 = 20. Attend the next 20 in a row and you are back to exactly 75%.
Does the 75% rule apply per subject or overall?
It depends on your college. Many apply the requirement to each subject separately, which means a comfortable overall percentage can hide one subject that is short. Check your college's regulations, and work the numbers out per subject to be safe.
Is this calculator free?
Yes. No sign-up, nothing to install. Cmpus, the app it comes from, is free too.
More from Cmpus
Cmpus does this for every subject, every day.
Mark a class in one tap and Cmpus keeps the count per subject, so you know before the shortage list goes up — not after. Free, no ads.
Start using Cmpus