On McMaster University's 12-point scale, 12 (A+) = 4.0, 11 (A) = 3.9, 10 (A−) = 3.7, 9 (B+) = 3.3, 8 (B) = 3.0, and so on down to 0 (F) = 0.0, according to the table McMaster's registrar publishes. To convert a whole GPA, convert each course with the chart, multiply by its units, and average. Don't divide your 12-point GPA by 3: the scales aren't evenly spaced, so that shortcut usually comes out too low.
The McMaster 12-point to 4.0 chart
This is the undergraduate grading table on the McMaster Registrar's grades page, including its percentage bands and 4.0 column.
| Letter | 12-point value | Percentage | 4.0 scale |
|---|---|---|---|
| A+ | 12 | 90–100 | 4.0 |
| A | 11 | 85–89 | 3.9 |
| A− | 10 | 80–84 | 3.7 |
| B+ | 9 | 77–79 | 3.3 |
| B | 8 | 73–76 | 3.0 |
| B− | 7 | 70–72 | 2.7 |
| C+ | 6 | 67–69 | 2.3 |
| C | 5 | 63–66 | 2.0 |
| C− | 4 | 60–62 | 1.7 |
| D+ | 3 | 57–59 | 1.3 |
| D | 2 | 53–56 | 1.0 |
| D− | 1 | 50–52 | 0.7 |
| F | 0 | 0–49 | 0.0 |
This chart is McMaster's. Another school that grades out of 12 may assign different letters or percentages, so check that school's own grading page before using these values.
How McMaster calculates a 12-point GPA
McMaster's method is the standard credit-weighted average, using "units" for credits:
- Course points = units × grade point. A B+ (9) in a 3-unit course earns 3 × 9 = 27 points.
- GPA = total points ÷ total GPA units.
- Non-numeric grades don't count. Courses graded P, NC, AUD or COM earn 0 course points and are left out of GPA units, so they neither raise nor lower the average.
The same method works for a term GPA or a cumulative GPA across all your terms.
Worked example: converting course by course
Priya, a fictional McMaster student, has these final grades:
| Course | Units | Letter | 12-point | 12-point × units | 4.0 value | 4.0 × units |
|---|---|---|---|---|---|---|
| Biology | 3 | A+ | 12 | 36 | 4.0 | 12.0 |
| Chemistry | 3 | A | 11 | 33 | 3.9 | 11.7 |
| Psychology | 3 | B+ | 9 | 27 | 3.3 | 9.9 |
| Physics (full year) | 6 | A− | 10 | 60 | 3.7 | 22.2 |
| Calculus | 3 | B | 8 | 24 | 3.0 | 9.0 |
| Total | 18 | 180 | 64.8 |
12-point GPA: 180 ÷ 18 = 10.0
4.0 GPA (course by course): 64.8 ÷ 18 = 3.60
That 3.60 is the number you get by applying McMaster's own 4.0 column to each course.
Two shortcuts that give the wrong answer
Using Priya's 10.0 average:
| Method | Result | Why it's off |
|---|---|---|
| Course-by-course (correct) | 3.60 | Uses the published value for every course |
Divide by 3 (10.0 ÷ 12 × 4) | 3.33 | Treats the scales as straight lines; McMaster's 4.0 column isn't |
| Look up the average in the chart (10 → 3.7) | 3.70 | Ignores the mix of grades behind the average |
The divide-by-3 shortcut is especially misleading near the top: an A (11) divided by 3 is 3.67, but McMaster lists it as 3.9. Students with mostly As and A−s can lose a quarter of a point or more this way.
How OMSAS and other applications handle 12-point grades
If you are applying to Ontario medical schools, the Ontario Universities' Application Centre (OUAC) runs OMSAS, which uses its own 4.0 scale. OMSAS converts each course grade with its Undergraduate Grade Conversion Table, using the scale listed for the university you attended. It also includes repeated courses when both attempts appear on your official transcript. That means your OMSAS GPA can differ from a McMaster cumulative GPA converted at home. Check the OMSAS GPA calculations page for its full rules.
Other applications differ again:
- Common App lets you report a GPA scale of 12 directly, since its scale menu covers whole numbers from 4 through 20 and 100. If your school reports a 12-point cumulative GPA, enter it on that scale rather than converting it.
- U.S. graduate schools often ask for the GPA exactly as your transcript shows it, or for a credential evaluation. Some ask for a 4.0 figure; follow the method they specify.
When a form doesn't say, report the original 12-point GPA and the scale, and keep your transcript's grading key handy. The international GPA converter guide covers evaluations and other countries' systems.
Step-by-step: convert your own transcript
- List every course with its units and letter grade from your transcript.
- Remove non-numeric grades (P, NC, AUD, COM), as McMaster does.
- Look up each grade's 4.0 value in the chart above.
- Multiply each 4.0 value by the course's units.
- Add those products, then divide by the total units.
- Keep two decimals and label it clearly, for example "3.60 (converted from McMaster 10.0/12 using the registrar's 4.0 column)."
Because McMaster's 4.0 column is close to the common U.S. letter-grade table, you can also enter your letter grades and units into the College GPA Calculator as a cross-check, with one adjustment: that calculator counts an A as 4.0, while McMaster lists A as 3.9. Expect the calculator to read slightly higher if you have several A grades, and use the hand calculation above as your figure. For the general weighting method, see the credit-hour weighting guide.
Frequently asked questions
What is a 10 out of 12 GPA on a 4.0 scale?
A single grade of 10 (A−) is 3.7 on McMaster's chart. A cumulative 10.0 depends on the grades behind it; in the example above it works out to 3.60. Convert course by course for your exact figure.
Is a 12-point GPA the same as a percentage?
No. Each 12-point value covers a percentage band (for example, 11 = 85–89 at McMaster), so you can't read a percentage straight off a GPA.
Is every Canadian university on a 12-point scale?
No. Canadian universities set their own scales, and many use other maximums. Check your own university's registrar page for its table.
Should I convert my McMaster GPA for applications?
Only if the application asks for a 4.0 figure. Otherwise report the original 12-point GPA with its scale, and let the school or a credential evaluator apply its own method. You can learn how other scales compare in the types of GPA scales guide.