Attendance Calculator
Check your attendance %, classes you can bunk, or classes needed to reach 75%
How to Use
- Enter the number of Classes attended and the Total classes held so far — take both from your college portal or attendance register.
- Set the Required attendance. It starts at 75%, the usual minimum in Indian colleges; change it if your institute uses a different rule.
- Read the result. If you are above the target, it shows how many classes you can miss in a row; if you are below, it shows how many classes you must attend without a break.
- Optional: switch on I know how many classes are left this term and enter the number of remaining classes to check whether the target is still reachable before exams.
- Results update as you type. Use the share button to save the link with your numbers, and recheck after every week of classes.
What this attendance calculator tells you
Most Indian colleges and schools will not let you sit for the end-semester or board exam unless your attendance is at least 75%. CBSE, for example, requires 75% attendance for Class 10 and 12 board exams under Rules 13 and 14 of its Examination Bye-Laws, with relaxation only for documented reasons such as serious illness or national-level sports. Universities and autonomous colleges set their own rules, and 75% is by far the most common figure. This calculator turns your attended and held classes into three useful answers: your current percentage, how many classes you can safely miss, and — if you are short — how many classes you must attend in a row to recover.
The formulas
Attendance is simply classes attended divided by classes held. When you miss a class, the number held goes up but the number attended does not; when you attend, both go up by one.
Classes you can miss = floor(attended ÷ target − held)
Classes to attend in a row = ceil((target × held − attended) ÷ (1 − target))
(target written as a fraction, e.g. 75% = 0.75)
If you enter the classes remaining in the term, the calculator also works out the minimum you must attend out of those remaining classes so that your final attendance on the last day is at or above the target: ceil(target × (held + remaining) − attended).
Worked examples
Above the target: you have attended 50 of 60 lectures, which is 83.33%. Missing 6 classes gives 50 ÷ 66 = 75.76%, still safe. Missing a 7th gives 50 ÷ 67 = 74.63%, below the line. So you can miss 6 classes.
Below the target: you have attended 30 of 50 lectures, which is 60%. After attending 30 classes in a row you reach 60 ÷ 80 = 75%; after 29 you would be at 59 ÷ 79 = 74.68%. So you need 30 consecutive classes. If only 20 classes are left in the semester, the best you can reach is 50 ÷ 70 = 71.43%, and the calculator tells you the target is no longer possible. If 40 are left, you need to attend at least 38 of them.
Minimum classes for 75% attendance
| Total classes in the term | Must attend (75%) | Can miss in total |
|---|---|---|
| 40 | 30 | 10 |
| 50 | 38 | 12 |
| 60 | 45 | 15 |
| 80 | 60 | 20 |
| 100 | 75 | 25 |
| 120 | 90 | 30 |
The table assumes you know the full number of classes for the term. Holidays, extra classes and cancelled lectures change the total, so it is safer to recalculate with the actual numbers every week or two.
Tips and things to check
- Subject-wise attendance: many universities check attendance separately for each subject, and for theory and practicals/labs separately. Run the calculator for each subject that is close to the limit.
- Rounding: this calculator does not round. Some colleges round 74.5% up to 75%, others do not — do not plan to sit exactly on the edge.
- Spread out your leaves: the “classes you can miss” figure is for missing them in a row starting now. Missing them spread across the term is equally safe, but missing more early leaves no buffer for illness later.
- Condonation: some universities condone a limited shortfall for medical or other documented reasons, usually with an application and sometimes a fee. The rules differ between universities, so read your institute’s ordinance or ask your class teacher before you count on it.
- Keep proof: submit medical certificates and duty-leave letters on time; late documents are often not accepted.