Attendance calculator (75% rule)
Calculated in your browser; nothing is uploaded. The answer assumes every future class counts the same as a past one.
Enter the number of classes you attended and the number held so far. The calculator shows your attendance percentage. If you are below the required percentage, it tells you how many classes in a row you need to attend to get back to it. If you are above, it tells you how many classes you could miss and still stay at or above it. The required percentage starts at 75 because that is the most common rule in Indian colleges, but you can change it.
Use the numbers from your college portal or attendance register, and use them per subject if your college checks attendance subject by subject. Many do, so being at 80% overall does not help if one subject is at 70%.
The formulas
Attendance % = attended / held x 100.
Classes needed to reach a target R% when you are below it: the smallest whole number x with (attended + x) / (held + x) at least R / 100. Rearranged, x = (R x held - 100 x attended) / (100 - R), rounded up.
Classes you can miss while staying at or above R%: the largest whole number y with attended / (held + y) at least R / 100. Rearranged, y = 100 x attended / R - held, rounded down.
Both assume the classes you attend or miss are the next ones in a row and each counts as one class. Labs or double periods that count as two need to be entered as two.
Worked examples at 75%
- Attended 30 of 45: 66.67%. You need (0.75 x 45 - 30) / 0.25 = 15 more classes in a row: 45 of 60 is exactly 75%.
- Attended 40 of 50: 80%. You can miss 40 / 0.75 - 50 = 3.33, so 3 classes: 40 of 53 is 75.47%. A fourth absence would make it 40 of 54, which is 74.07%.
- Attended 27 of 36: exactly 75%. You can miss none; one more absence gives 27 of 37, 72.97%.
- Target 85% with 50 of 70 attended (71.43%): you need (0.85 x 70 - 50) / 0.15 = 63.3, so 64 classes in a row.
About the 75% rule
Many Indian universities and colleges require 75% attendance to sit the end-semester exam, and some allow a small condonation for medical or other approved reasons. The exact rule, whether it is per subject or overall, and what counts as an approved absence are set by your university and college, so check your regulations or ask your department. This calculator only does the arithmetic; it cannot tell you whether you will be allowed to write an exam.
How to use the attendance calculator
- Type the classes you attended and the classes held so far, from your portal or register.
- Leave the required percentage at 75, or change it to your college's rule.
- Read the result: your current percentage, and either the classes you need or the classes you can miss.
Related tools
FAQ
- How do I calculate my attendance percentage?
- Divide the classes you attended by the classes held and multiply by 100. For example, 30 of 45 is 66.67%.
- How many classes do I need to attend to reach 75%?
- Use (0.75 x held - attended) / 0.25 and round up. With 30 of 45 that is 15 classes in a row, which gives 45 of 60.
- How many classes can I bunk and stay above 75%?
- Use attended / 0.75 - held and round down. With 40 of 50 that is 3 classes. The calculator does this for you.
- Is 75% attendance compulsory everywhere?
- No. It is common in Indian colleges, but the percentage and how it is applied are set by each university and college. Check your own regulations.
- Does the calculator know my college's rules?
- No. It only does the arithmetic on the numbers you enter. Condonation, medical leave and per-subject rules depend on your college.
- Is anything I type saved?
- No. The calculation runs in your browser. Only an anonymous count that the tool was used is recorded.