OpusDesk Hub Tools

Attendance Calculator

Check your attendance and the classes needed to reach your own target.

Enter the attendance target that applies to you. This is a class-count calculation, not a statement of your institution’s eligibility rules.

Count completed classes you attended.

Include attended and missed classes.

Required: 0–100%, up to two decimal places.

Use a known schedule to check whether your target is still possible.

What this tool does

Calculate your current class attendance, how many consecutive classes you need to attend, and how many you can miss while meeting an entered target.

How to use Attendance Calculator

  1. Enter completed classes. Enter attended and conducted class counts. Use one consistent unit: classes, not a mixture of classes and hours.
  2. Set your target. Enter the percentage that applies to you. Add remaining classes only if you know the schedule; no university threshold is assumed.
  3. Read the scenario. Calculate to see the current fraction, consecutive attendance needed and maximum extra absences. A target may be impossible within the remaining schedule.

How this tool works

Current percentage is A/T × 100. For a target fraction q between 0 and 1, catch-up is max(0, ceil((qT − A)/(1 − q))). When already at target, missable classes are floor(A/q − T). Zero conducted classes and 0%/100% targets use explicit boundary rules.

  • Engine: Integer class counts and exact basis-point threshold arithmetic
  • Supported input: whole attended and conducted class counts, 0–100% target with up to two decimals, optional whole remaining-class count
  • Output: attendance percentage, class counts and formula breakdown

Worked example

Input: 30 attended, 50 conducted, target 75%

Output: 60% current attendance; 30 consecutive attended classes reach 60/80 = 75%.

Limits, edge cases, and troubleshooting

Use the remaining-class field to distinguish eventual mathematical catch-up from what is possible this term. With only 20 classes left in this example, the maximum is 50/70 = 71.4286%.

  • Class-count inputs are limited to one billion to keep results within supported arithmetic bounds.
  • No university rules, excused-absence policy or subject eligibility are inferred.
  • Catch-up assumes every additional class is attended; display rounding never determines eligibility.

When to use another workflow

Use the institution's official attendance portal when hours, excused sessions, practicals or separate subject requirements affect eligibility.

OptionBest forTrade-off
This browser toolQuick, private, one-off workLimited by browser memory and the documented feature set
Desktop or command-line toolBatch jobs and repeatable automationRequires installation and setup

Verification

Implementation checked on 2026-09-16. Unit tests and local browser checks covered 30/50 at 75% (30 catch-up classes), zero conducted classes, 0% and 100% targets, invalid counts and a finite remaining schedule. Narrow layouts and a keyboard-only calculation were checked.

Supported inputs and limits

  • whole attended and conducted class counts
  • 0–100% target with up to two decimals
  • optional whole remaining-class count
  • Class-count inputs are limited to one billion to keep results within supported arithmetic bounds.
  • No university rules, excused-absence policy or subject eligibility are inferred.
  • Catch-up assumes every additional class is attended; display rounding never determines eligibility.

Frequently asked questions

Is 75% a universal attendance requirement?

No. The example uses 75% only to demonstrate the arithmetic. Enter your own target and check subject-specific, excused-absence and eligibility rules with your institution.

Can I recover exact 100% after missing a class?

No finite number of additional attended classes removes an earlier absence from the conducted total. If every conducted class was attended, catch-up is zero. If no classes were conducted, one attended class establishes a percentage.

Is information sent to a server?

Tool inputs are processed in this browser. This product does not use analytics or send your input to an external API. Clicking an external website link still visits that website.

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