Calculate Grades Based on Points
Points-based grading is one division: everything earned over everything possible. This page opens with a term already in the boxes, 178 of 200, 88 of 100, 82 of 100 and 145 of 150, which totals 493 of 550, or 89.64% and a B+, two points short of an A-. Add a row for every assignment, remove one to see what dropping a score would do, and the total, the percentage and the letter follow every keystroke.
- Mode
- Scale
89.64% (B+) from 493 of 550 points on the plus / minus scale.
One row per assignment: points earned over points possible. Press Enter in any field to add another line.
- Percentage
- 89.64%
- Letter
- B+
- Points earned
- 493
- Points possible
- 550
Worked examples
Each one runs through the same code the page above does, on the plus / minus scale, so switching the scale moves them too.
The scale in use
Every band includes its own floor and runs up to the next one. On this scale, 89.99% is B+ and 90% is A-. The displayed two-decimal percentage does not determine the letter.
| Letter | Percentage band |
|---|---|
| A+ | 97% and above |
| A | 93% up to 97% |
| A- | 90% up to 93% |
| B+ | 87% up to 90% |
| B | 83% up to 87% |
| B- | 80% up to 83% |
| C+ | 77% up to 80% |
| C | 73% up to 77% |
| C- | 70% up to 73% |
| D+ | 67% up to 70% |
| D | 63% up to 67% |
| D- | 60% up to 63% |
| F | 0% up to 60% |
Common questions
- How do you calculate a grade based on points?
- Add every point earned, add every point possible, and divide the first by the second. For 178 of 200, 88 of 100, 82 of 100 and 145 of 150 that is 493 divided by 550, or 89.64%. The letter comes from the scale you choose: on the plus/minus scale, 89.64% is a B+, and the line under the headline says two more points would make it 495 of 550, 90.00% and an A-.
- Why is that different from averaging the percentages of each assignment?
- Because points give a big assignment a bigger say, which is the whole point of a points-based course. A 10-point quiz scored 10 out of 10 and a 200-point exam scored 160 out of 200 is 170 out of 210, which is 80.95%. Averaging 100% and 80% gives 90% and describes a course that does not exist unless the syllabus says both are worth the same, in which case the weighted mode is the one that says so.
- What happens to a row I leave empty?
- It is skipped, not scored zero. A row that has a name but no numbers is skipped too, so you can list the assignments still to come without them dragging the total down. A row with one of the two numbers filled in is the one case that stops: it says which row, and what to enter, because half a row is more likely a typo than a plan.
- How do I enter extra credit?
- Points mode cannot take more earned than possible, so a bonus that pushes a score past 100% has nowhere to go in a row: entering 22 out of 20 is refused, and the message names the row and both numbers, because a transposed pair is far more often what that is. Real extra credit belongs in Weighted mode, which does accept a category above 100: a category scored 105 at a weight of 20 raises the average exactly as your instructor's bonus does.
- How many points do I need for the next letter?
- The line under the percentage says so continuously: it names the next band up, the points needed to reach it, and what the total and percentage would be. It is arithmetic on the totals you entered, so it cannot know about an assignment you have not listed or a curve nobody has applied yet.
- Can I use a 1000-point course or average two scores?
- Yes. Enter the actual earned and possible points for each assignment; totals can exceed 1000. The percentage is the total earned divided by total possible, so assignments with different maximum points are not averaged equally. Use Weighted mode with equal category weights only when equal importance is the intended rule.
Percentages use the scores and weights you enter and are displayed to two decimals. Letter grades use the computed percentage against the selected scale. Attainable final-score targets round upward to the next 0.01% and assume one remaining component scored from 0% to 100%. Curves, dropped scores and institutional rounding policies must come from your syllabus.