No ads, no sign-upChecked 2026-08-28

Academic Semester Days Calculator

Result

75teaching days

Result: 75 teaching days

Enter the first and last day of the term and how many non-teaching weekdays it contains. A US fall semester from 25 August to 15 December 2026 spans 113 calendar days, 32 of them weekends; with 6 holidays that leaves 75 instructional days — the 15-week Carnegie baseline.

The numbers at a glance

Held fixed: First day of the semester 2026-08-25, Last day of the semester 2026-12-15.

Non-teaching weekdaysResult
081
279
477
6Your value75
873
1071
1269

Worked examples

Case 1
First day of the semester
20690
Last day of the semester
20802
Non-teaching weekdays
6

75

Open with these values
Case 2
First day of the semester
20820
Last day of the semester
20838
Non-teaching weekdays
1

12

Open with these values
Case 3
First day of the semester
20703
Last day of the semester
20714
Non-teaching weekdays
0

10

Open with these values

How it's calculated

instructional days = weekdays in the term − non-teaching weekdays

  1. StepEnter the first and the last calendar day of the term. Both count.
  2. StepEvery Saturday and Sunday drops out of the span.
  3. ResultSubtract the non-teaching weekdays — holidays, breaks, a reading week.

What this number means

An instructional day is a scheduled day on which teaching, reading or examinations take place. The count starts from the full calendar span, both end dates included, removes every Saturday and Sunday, and then removes the non-teaching weekdays you enter. With the preset term — 25 August to 15 December 2026 — that is 113 calendar days, 32 of them at the weekend, so 81 weekdays remain; six non-teaching weekdays bring it to 75. That number is not a coincidence. Seventy-five is the Carnegie baseline for a 15-week semester on a five-day week, the figure US credit-hour accounting is built around, and it is why the old calculator used exactly this term as its default. Two things this page does not do. It has no holiday calendar of its own: how many teaching days a Thanksgiving week or a reading period costs differs by institution, so you enter that number yourself. And it counts days across the whole term, not the meetings of a single course — a Tuesday/Thursday class meets on a fraction of these days. The convention itself is regional. German terms are cut into a Vorlesungszeit of roughly 14 to 15 weeks next to a lecture-free period, and workload there is measured in Semesterwochenstunden rather than in days, so the 75-day yardstick does not carry over even though the arithmetic does.

75 days is the Carnegie baseline, not a law

A standard 15-week semester on a five-day week comes to 75 instructional days, which is the figure US credit-hour accounting is built around. It is a convention: your registrar's calendar is the binding one.

German terms are cut differently

A German Vorlesungszeit runs roughly 14 to 15 weeks next to a lecture-free period, and workload is counted in Semesterwochenstunden rather than in days. The arithmetic here still works; the 75-day yardstick does not transfer.

Exam and reading days usually count

US institutions count final-exam periods and reading days as instructional days for accreditation. If you are mapping actual lectures for a syllabus, enter them as non-teaching weekdays instead.

A holiday on a weekend costs nothing

Only weekdays are in the count to begin with, so a Saturday holiday changes nothing. Enter it only if your institution observes it on the adjacent Friday or Monday.

Commonly misread

A 15-week semester has 105 days, because 15 × 7 = 105.

Weekends are not instructional days. Fifteen weeks of five teaching days give 75.

I should also subtract the holidays that fall on a Saturday or Sunday.

No — those days were never counted. Subtract only the non-teaching days that land on a weekday.

Final exam week is not instruction, so it does not count.

In US credit-hour accounting exam periods do count as instructional days. Leave them in unless you are counting lectures only.

The number tells me how often my Tuesday/Thursday class meets.

It does not. This page counts teaching days across the whole term, not the meetings of one class.

Reference table

TermCalendar daysWeekendsInstructional days
25 Aug – 15 Dec 2026, 6 holidays1133275
25 Aug – 15 Dec 2026, no holidays1133281
2 – 20 Jan 2027, 1 holiday19612
7 – 18 Sep 2026, no holidays12210

Questions

What is an instructional day?

Any scheduled calendar day on which teaching, reading days or final exams take place. Weekends and official non-teaching days are excluded. Definitions vary, so check your institution's academic calendar.

How many teaching days are in a 15-week semester?

Seventy-five, assuming a regular five-day academic week. That is the Carnegie baseline behind the 45 academic contact hours of a standard 3-credit course.

Do final exams and reading days count?

In US credit-hour accounting, yes — they are counted as instructional days for accreditation. If you are mapping actual lectures instead, enter them as non-teaching weekdays.

What if a holiday falls on a weekend?

Then it costs nothing, because weekend days were never in the count. Enter it only if your institution observes it on the adjacent Friday or Monday.

Does this work for a German semester?

The arithmetic does, but the yardstick does not. A German Vorlesungszeit runs about 14 to 15 weeks beside a lecture-free period and is measured in Semesterwochenstunden, not in instructional days.

Sources and last check

  1. aa.usno.navy.mil

Information, not professional advice.