Attendance calculator
Your attendance percentage is classes attended ÷ classes held × 100. Enter your numbers below to see how many classes you can still miss, or how many you need to attend in a row to get back to your target.
Where do I stand?
Count every class held so far, including the ones you missed.
Planning a whole semester?
If you know how many classes a subject will have in total.
How the calculator works
Attendance percentage
attendance % = attended ÷ held × 100
Attending 32 of 40 classes is 32 ÷ 40 × 100 = 80%.
How many classes can I miss?
Each class you miss still counts as held, so your percentage drops. The most you can miss while staying at your target is:
can miss = ⌊ attended × 100 ÷ target − held ⌋
With 32 of 40 and a 75% target: 32 × 100 ÷ 75 − 40 = 2.67, rounded down to 2 classes. After missing both you would be at 32 ÷ 42 = 76.19%; a third would take you to 74.41%.
How many classes do I need to attend to reach 75%?
If you are below target, every class you attend from now on raises your percentage. The number you need in a row is:
need = ⌈ (target × held − attended) ÷ (1 − target) ⌉
Here the target is written as a fraction (75% = 0.75). With 28 of 40 (70%): (0.75 × 40 − 28) ÷ 0.25 = 8 classes, which brings you to 36 of 48 = 75%. If the term ends before that, use the attendance recovery calculator.
Common questions
What attendance percentage do I need?
It depends on your school. 75% is a common minimum at many colleges, and some ask for 80% or more. Check your institution's attendance rules or ask your department, then enter that number as your target.
Do cancelled classes count?
Usually not. A class that never took place was not held, so leave it out of both numbers. Classly lets you mark a class as cancelled so it is left out automatically.
Should I work it out per subject or overall?
Most schools apply the rule to each subject separately, so a high overall percentage can still hide one subject below the limit. Calculate each subject on its own.
Why does the calculator say I can miss 0 classes?
You are at or just above your target, and missing even one more class would drop you below it. Attend the next class to build a margin.