Attendance Calculator
Find out exactly how many classes you can miss and still meet your attendance requirement — or calculate your current attendance percentage. Works for any course, school, or threshold.
How to Calculate Attendance
Two formulas cover every attendance question you'll encounter.
Max absences allowed
Example: 36 classes, 75% required → ⌈36 × 0.75⌉ = 27 must attend → can miss 9
Attendance percentage
Example: 28 attended out of 36 total → 28 ÷ 36 × 100 = 77.8%
How Many Classes Can I Miss? — Quick Reference
Maximum absences allowed at each common attendance threshold. Numbers are rounded using the ceiling rule — the minimum classes you must attend is always rounded up.
Numbers shown are maximum absences. Green = comfortable buffer, yellow = use caution, red = no room left.
What Happens If You Miss Too Many Classes?
Consequences vary significantly by institution and course type.
Most US colleges delegate attendance policy to individual professors. Consequences range from grade deductions (e.g. −5% per absence over the limit) to automatic course failure or forced withdrawal. A forced withdrawal (W) doesn't affect GPA but appears on your transcript and may affect financial aid.
Nursing, medical, dental, pharmacy, and PA programs typically require 85–90% attendance. Missing mandatory labs or clinical sessions often cannot be excused or made up. Exceeding absence limits may result in removal from the program.
Many states have compulsory attendance laws. Excessive absences (typically 10+ per semester) can result in loss of course credit, grade retention, or referral to a truancy officer. Some states require excused documentation for any absence beyond 3–5 per semester.
Attendance in online courses is often measured by participation — completing assignments, joining synchronous sessions, or logging into the LMS. Missing synchronous sessions or failing to submit work on time is treated as an absence even if there is no physical classroom.
Frequently Asked Questions
Common questions about attendance requirements and absence policies.
How do I calculate how many classes I can miss?
Multiply your total number of classes by the required attendance percentage to find the minimum number you must attend. Subtract that from the total to get your maximum allowed absences. For example, with 36 classes and a 75% requirement: 36 × 0.75 = 27 classes required, so you can miss 36 − 27 = 9 classes.
What is the formula for attendance percentage?
Attendance percentage = (Classes Attended ÷ Total Classes) × 100. For example, if you attended 28 out of 36 classes: 28 ÷ 36 × 100 = 77.8%. Most schools round to one decimal place.
What happens if I go below the required attendance?
Consequences vary by institution. In college, falling below the minimum attendance requirement can result in an automatic grade deduction, a forced withdrawal (W grade), or a failing grade in the course regardless of your exam scores. Some professors have stricter policies than the institutional minimum — always check your syllabus. In high school, excessive absences can result in grade retention or loss of credit.
What is a typical college attendance requirement?
Most US colleges leave attendance policy to individual professors, but common thresholds range from 75% to 90%. Community colleges often enforce 75–80%. Professional programs (nursing, medicine, law) typically require 85–90%. Some courses — especially labs, studios, and performance classes — require 90%+ due to the hands-on nature of the work.
Does it matter why I missed class?
Yes — most institutions distinguish between excused and unexcused absences. Excused absences (illness with documentation, bereavement, religious observance, official university travel) typically don't count against your attendance record. Unexcused absences always count. Some professors offer no distinction at all and count every absence equally. Check your syllabus carefully.
Can I make up missed classes?
It depends on your institution and professor. Many professors allow makeup work for excused absences only. Some offer "attendance recovery" through office hours, extra assignments, or recorded lecture reviews. Labs and studio classes are often impossible to make up due to equipment and scheduling constraints. When in doubt, email your professor as soon as possible after an absence.
How do I calculate attendance if classes have different credit weights?
Most attendance policies count each class session equally regardless of credit weight. A 3-credit course that meets three times per week counts each session as one class. If your institution uses hours rather than sessions — common in professional programs — multiply each session by its duration and calculate the percentage of total hours attended.
What counts as an absence vs a tardy?
Policies vary. Many professors count arriving more than 10–15 minutes late as a tardy, and two or three tardies equal one absence. Leaving early before class ends is often treated the same as arriving late. Some professors mark anyone not present at roll call as absent, regardless of when they arrive. The safest approach is to check your syllabus and ask your professor directly.