The common convention — and four published variants
The most widely used convention splits each 10-point band into plus/minus steps. It is a convention, not a rule: no official body decrees it, and real schools publish different cutoffs. The table below lines up the common convention against four published scales, all expressed as the lowest percent that earns each letter.
| Letter | Common plus/minus | Straight 10-point | CU Denver (93) | UTC (90) | National (94) | UF Pharmacy (92.50) |
|---|---|---|---|---|---|---|
| A+ | 97–100 | — | — | — | — | — |
| A | 93–96 | 90–100 | 93–100 | 90–100 | 94–100 | 92.50–100 |
| A− | 90–92 | — | 90–92.9 | — | 90–93.99 | 89.50–92.49 |
| B+ | 87–89 | — | 87–89.9 | — | 87–89.99 | 86.50–89.49 |
| B | 83–86 | 80–89 | 83–86.9 | 80–89 | 83–86.99 | 82.50–86.49 |
| B− | 80–82 | — | 80–82.9 | — | 80–82.99 | 79.50–82.49 |
| C+ | 77–79 | — | 77–79.9 | — | 77–79.99 | 76.50–79.49 |
| C | 73–76 | 70–79 | 73–76.9 | 70–79 | 73–76.99 | 72.50–76.49 |
| C− | 70–72 | — | 70–72.9 | — | 70–72.99 | 69.50–72.49 |
| D+ | 67–69 | — | 67–69.9 | — | 67–69.99 | 66.50–69.49 |
| D | 63–66 | 60–69 | 63–66.9 | 60–69 | 63–66.99 | 62.50–66.49 |
| D− | 60–62 | — | 60–62.9 | — | 60–62.99 | 59.50–62.49 |
| F / E | Below 60 (F) | Below 60 (F) | Below 60 (F) | Below 60 (F) | 0–59.99 (F) | Below 59.50 (E) |
“—” means that letter does not exist on that scale. UF Pharmacy uses E, not F, as its failing letter. National’s graduate scale differs (F below 73, no D grades) and is not shown here.
Same percent, different letters
Two percents show why the scale selector matters:
| Percent | Common | Straight | CU Denver | UTC | National | UF Pharmacy |
|---|---|---|---|---|---|---|
| 92% | A− | A | A− | A | A− | A− |
| 59.6% | F | F | F | D* | F | D− |
*UTC rounds half-up to a whole percent first, so 59.6% becomes 60% → D. Without rounding it would be F. UF Pharmacy rounds X.495+ up to X.50; 59.6% needs no rounding to land in its D− band (59.50–62.49).
Boundary and rounding rules
Bands above are written as published. Two details decide borderline cases:
- Endpoint notation. CU Denver writes “90–92.9” while National writes “90–93.99”. Both mean the same thing in practice — A− starts at 90 and A starts at the next cutoff — but the notation differs. This calculator uses lower bounds: a percent earns the letter whose lower bound it reaches.
- Rounding. Rounding is the publishing school’s rule for that scale, not a universal step. The common convention assumes no rounding (89.5% stays B+). UTC rounds half-up to a whole percent (89.5% → 90% → A). UF Pharmacy rounds X.495+ up to X.50. If your syllabus states no rounding rule, do not assume one.
What varies by school
- The A cutoff: 90 vs 92.50 vs 93 vs 94 — all documented above.
- Plus/minus vs straight letters: some schools split bands; some do not.
- Whether A+ exists at all — and whether it carries bonus points (ASU 4.33, LSU 4.3, Purdue 4.0, UF/UT none).
- Whether C− / D+ / D− exist: ASU has none of the three.
- The failing letter: E (ASU, UF) vs F (LSU, Purdue, UT Austin) — same 0.00 value, different letter.
Assumptions on this page
- Default scale: the common plus/minus convention, labelled as a convention — not any school’s rule.
- Rounding: applied only where the publishing school states it (UTC, UF Pharmacy). Other scales use the entered percent as-is.
- National scale: undergraduate only. The graduate scale differs and is not modelled.
- Program scales: CU Denver, UTC, and UF Pharmacy scales are those programs’ scales — never the university’s scale.
Common mistakes
- Treating the common scale as “the US scale.” There is no US-wide scale. The common scale is a convention.
- Calling a program’s scale the university’s scale. UF Pharmacy’s 92.50 cutoff is a PharmD program scale, not “the UF scale.” UF’s catalog publishes no percent bands at all.
- Assuming rounding. 89.5% is B+ on the common convention and A under UTC’s rounding. The syllabus decides.
- Reading a percent as a GPA. A percent maps to a letter; the letter maps to grade points only under a specific school’s table. 88% → B+ gives 9.99 quality points for 3 credits at ASU/UF/UT but 9.90 at LSU/Purdue.
- Applying one school’s table to another. A+ = 4.33 is ASU’s value, not Purdue’s (4.0) or UF’s (no A+).
Sources: CU Denver Modern Languages grading scale · UTC DPT grading policies · National University grading scale · UF College of Pharmacy course policies. Full walkthrough: How to Convert Percentage to Letter Grade. Grade points by university: ASU GPA Calculator, LSU GPA Calculator, Purdue GPA Calculator, UF GPA Calculator, UT Austin GPA Calculator.