Grading Scale Explained: A–F, Percentages, and GPA

The Standard A–F Grading Scale

Most US schools run on the same basic letter-grading system, even when the exact cutoffs differ from classroom to classroom: a 100-point scale gets converted into a small set of letters that stand in for how a student performed on a test or in a class. Every teacher's syllabus should spell out where those lines fall, but the table below is the version used almost everywhere as the default.

What Each Letter Grade Means

Honor-roll lists and merit scholarships are usually reserved for students posting an A, since that grade signals strong comprehension and real command of the material rather than a lucky guess. It's also the baseline most competitive college programs expect to see repeated across a transcript, and it's the grade that drives class rank and weighted GPA calculations at schools offering AP or Honors sections. A B still reads as good performance with above-average understanding, giving a solid foundation at most four-year universities, while a C is genuinely average — a passing grade that keeps a cumulative GPA intact but starts to limit which prerequisites and graduate programs stay realistically open.

A D is technically passing but reflects below-average performance: plenty of core courses — especially in nursing or engineering — require a C or better, so a D can quietly disqualify continuation in a specific major even though the transcript still shows a passing grade rather than a fail. An F means failing outright, and unlike a D it usually can't be patched with extra credit — it requires retaking the course, and only a school's own grade-forgiveness or repeat policy determines whether the new grade replaces the old one on the record.

Plus and Minus Grades Explained

Not every school bothers with plus and minus modifiers on top of the main letter grades — some report a flat A/B/C/D/F and nothing else — but where they're used, each letter splits into up to three variations, giving a finer read on where a student actually landed. F is the one exception: there's no F+ and no F−, since a fail doesn't get graded on a curve of its own.

The gap between a B+ and a B− works out to 0.6 GPA points, which sounds small until it's multiplied across a full semester — six classes at the low end of each letter instead of the high end can shift a report card by nearly half a point, and that gap compounds over four years into a genuinely different GPA range. Schools don't even agree on where the thresholds sit for the highest grade: an A+ might require 97% at one school and 96.5% or 98% at another, so the exact cutoff is always worth checking against a specific syllabus rather than assumed.

Why Is There No E Grade?

The letter-grading system is often traced back to a school in Massachusetts — Mount Holyoke College, around 1897 — where the original scale reportedly included an E for a failing mark. The commonly cited origin story is that both parents and teachers misread E as standing for "Excellent," which defeated the entire point of the letter. That story is repeated across several sources but isn't tied to a primary document, so it's worth treating as the commonly cited explanation rather than a confirmed fact.

"F for Fail" solved the confusion because it's unambiguous, and by the early 1900s most American schools had standardized on A through D plus F, with E dropped from the mainstream scale. A handful of programs still use it in narrow contexts today, but for the vast majority of US classrooms, F has been the failing grade for well over a century.

How the Grading Scale Connects to GPA

A grade point average is the letter-grade table above converted into a single number, typically running from 0.00 to 4.00, and it's the figure checked against graduation requirements: undergraduates generally need at least a 2.0 GPA to graduate, while graduate students — especially those holding a scholarship — are usually held to a 3.0 GPA floor.

The GPA calculation weights every grade by its course credits — a 4-credit lab course pulls harder on the final number than a light 1-credit seminar does — which is where credit hours and quality points come in. As a practical example: five 3-credit courses graded A, A, B+, B, and C add up to roughly 48.9 quality points over 15 credits, for about a 3.26 GPA — noticeably lower than the 3.575 it would have been without that one C, exactly the kind of trade-off worth watching before a big test in a heavy-credit course.

What Counts as a Passing Grade?

The honest answer depends on the school and the goal. A passing grade at most US high schools simply means clearing F and earning credit toward graduation, but college raises the bar considerably. Many major-specific courses, especially in pre-med or engineering tracks, quietly require a C or better rather than treating a bare pass as good enough, since a D signals foundational gaps for building on in the next course.

That leaves D grades sitting in genuinely ambiguous territory: technically passing through most programs, but often not counted toward major requirements. It matters for real stakes too — financial aid and good academic standing can hinge on avoiding too many D's, and international students in particular should confirm with their academic advisors whether a D-range grade will even transfer for credit, since many receiving institutions and pass/fail courses won't accept it. A 65% specifically tends to land right in this D range on most standard scales — technically passing, but rarely comfortable.

How Grading Scales Vary by School and Class Type

A student earning 91% might land an A at one school and a flat B+ at the next, because the A threshold genuinely moves between institutions — always check the actual course syllabus rather than assuming the standard table applies. AP and Honors courses frequently run on a weighted scale instead, where an A is worth 5.0 rather than 4.0, and a few schools use a 4.33 scale that adds a small bonus for an A+; competitive fields like medicine and law often apply stricter cutoffs on top of whichever base scale a program uses.

There's a workload side to this that rarely comes up in grading-scale conversations: a credit hour is nominally one hour of weekly classroom instruction, but most guidelines put the real time commitment at roughly triple that once outside work is counted — a four-credit course can carry study hours well beyond its listed credit number. Add that up across a full 15-credit semester and the actual weekly workload gets close to 45 hours, the pace needed to reach the roughly 120 total credits most four-year degrees require on schedule.

Beyond A–F: Standards-Based and Weighted Grading

Standards-based grading — sometimes called mastery or competency-based grading — skips the traditional 0–100 point system in favor of a small set of proficiency levels, with labels like "Exceeds Standard," "Meets Standard," and "Approaching Standard" reporting whether a skill was actually demonstrated, rather than compressing it into a single letter. A handful of liberal-arts schools go a step further with narrative evaluations — written comments instead of any letter or number at all.

Schools that do want to convert a standards-based result back into something that fits a normal GPA generally lean on a straightforward percentage method rather than more complex averaging approaches, mainly because it's the easiest one to explain consistently across an entire school, even if it loses some of the nuance those other methods were built to capture.