Attendance Percentage Calculator
Your attendance %, and how many classes you can miss.
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Enter the classes you've attended and how many have been held to get your attendance percentage instantly. Set a target — many colleges require 75% — and the calculator tells you how many more classes you can safely miss, or must attend, to reach it.
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How to Calculate Attendance Percentage — The Quick Answer
Divide the classes you attended by the total classes held, then multiply by 100. To work out how many you can still miss, solve for the largest number of absences that still leaves you at your target.
Shortcut
attendance % = (attended ÷ held) × 100
Attendance at a 75% target
| Attended / Held | % | Status |
|---|---|---|
| 42 / 50 | 84% | can miss 6 more |
| 36 / 50 | 72% | must attend 6 to recover |
| 45 / 60 | 75% | right on the line |
The maths that matters most: to stay at or above a target t, you can still miss floor(attended ÷ t − held) classes. Once you're below the target, you must attend future classes at a higher rate to climb back — the further below you are, the steeper that climb.
How It Works
The Formulas
Percentage, and the skip/attend planner
Formula
attendance % = (attended ÷ held) × 100 classes you can miss = ⌊(attended − (target ÷ 100) × held) ÷ (target ÷ 100)⌋ classes you must attend = ⌈((target ÷ 100) × held − attended) ÷ (1 − target ÷ 100)⌉
Variables
Your current percentage
The straightforward share of classes you've attended. If you attended 42 of 50, that's 42 ÷ 50 × 100 = 84%.
Classes you can still miss
When you're above target t, this is the largest number of further classes you can skip and still finish the term at or above t. With 42 of 50 attended at a 75% target: floor(42 ÷ 0.75 − 50) = floor(56 − 50) = 6 absences still allowed.
Classes you must attend
When you're below target, this is how many of your remaining classes you need to attend to climb back to it. It rises quickly the further below you are, and can exceed the classes left — meaning the target is out of reach.
Note: Attendance rules vary — some institutions require 75%, some 80%, and many allow documented exceptions. Use this as a planning aid and check your school's official policy.
Worked Example
42 of 50 classes attended, target 75%
Current percentage
42 ÷ 50 × 100 = 84%.
How many more you can miss at 75%
You can stay at 75% as long as attended ÷ total ≥ 0.75. With 42 attended, that allows up to 56 classes held — so 6 more (56 − 50) can be missed.
Check
Miss 6 and the term ends at 42 ÷ 56 = 75% exactly — the last allowed absence.
Reference Guide
| unit | value | note |
|---|---|---|
| 42 / 50 | 84% | current attendance |
| Target 75% | above target | room to miss classes |
| 37 / 50 | 74% | just below target |
Key Features
Last updated: October 5, 2026
Creators
Computer Scientist & Developer Tools Author
Reviewers
Technical Reviewer
Table of Contents
Quick Facts
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Frequently Asked Questions
How do I calculate my attendance percentage?
Divide the number of classes you attended by the total number of classes held, then multiply by 100. If you attended 42 of 50 classes, your attendance is 42 ÷ 50 × 100 = 84%.
How many classes can I miss and still keep 75%?
At a 75% target you may miss up to 25% of the classes. If 50 classes have been held, that's 12 absences allowed, so with 8 already missed you can miss 4 more. Add the term's total classes to get a figure for the whole course.
I'm below the required attendance — how many classes must I attend to recover?
Enter the total number of classes in the term and the calculator works it out: it finds how many of your remaining classes you must attend to bring the running total back to your target. If that number is greater than the classes you have left, the target can no longer be reached from attendance alone.
What is a typical required attendance percentage?
Many schools and universities require a minimum of 75%, though some set 80% or other thresholds, and medical or extenuating-circumstance allowances often exist. Check your institution's policy — the calculator lets you set any target so it matches your situation.