Grade Distribution Calculator

You paste in your students' scores as a comma-separated list and set minimum thresholds for each letter grade (A, B, C, D). The calculator counts how many students fall into each grade band, then divides by the total to give you the percentage distribution. It also shows the class average, highest, and lowest scores.

The most common scale sets A at 90–100%, B at 80–89%, C at 70–79%, D at 60–69%, and F below 60%. Some instructors use a stricter scale (A starts at 93%) or a more generous one — the calculator lets you customize all four cutoffs to match your own syllabus.

Yes. After reviewing the distribution, if too many students are scoring in the D or F range, it may signal that a curve is appropriate. You can experiment with your A, B, C, and D thresholds to see how shifting the cutoffs changes the distribution before deciding whether to curve.

It depends on context. A linear scale (fixed percentage cutoffs) is straightforward and consistent, but it doesn't account for exam difficulty. If a test was unusually hard, many educators apply a curve so that the class average aligns with a target score, which can produce a more representative distribution.

Convert your raw scores to percentages before entering them (divide the student's score by the total possible points and multiply by 100). For example, a score of 42 out of 50 would be entered as 84.

The class average gives a single summary statistic, but it doesn't reveal the spread of scores. A class average of 75% could mean most students scored near 75%, or it could hide a bimodal distribution with many A's and F's. The full grade breakdown and chart show you the complete picture.

Yes — you can paste in as many scores as you need, separated by commas or placed on separate lines. There's no hard limit on the number of students, making it suitable for both small seminars and large lecture courses.

Each grade's percentage is calculated by dividing the number of students in that grade band by the total number of valid scores entered, then multiplying by 100. For example, if 8 out of 30 students scored 90 or above, the A percentage would be 26.7%.