Rubric Grade Calculator
Score a rubric, then see the percentage and letter grade under three conversion methods side by side — so a 2 out of 4 doesn't quietly become an F. Works for one student or a whole class.
Rubrics and scores stay in your browser — nothing is uploaded or shared.
1 · Rubric setup (levels and criteria, click to edit)
2 · Conversion settings (floor, table, letter scale)
4 → 100% · 3 → 83.3% · 2 → 66.7% · 1 → 50%
3 · Score
0 of 4 criteria scored.
Conversion chart for this rubric
| Avg | Linear | Floor | Table |
|---|---|---|---|
| 4.0 | 100% A | 100% A | 100% A |
| 3.5 | 87.5% B | 91.7% A | 95% A |
| 3.0 | 75% C | 83.3% B | 85% B |
| 2.5 | 62.5% D | 75% C | 77% C |
| 2.0 | 50% F | 66.7% D | 70% C |
| 1.5 | 37.5% F | 58.3% F | 65% D |
| 1.0 | 25% F | 50% F | 60% D |
Why a straight percentage distorts a 4-point rubric
The obvious conversion is points earned ÷ points possible. It works for a test, where each point is a question answered correctly. A rubric level is different: it is a description of the work — Exceeds, Meets, Approaching, Beginning — and dividing by four turns those descriptions into 100%, 75%, 50% and 25%. On a standard 10-point scale that makes Meets a C and both Approaching and Beginning an F. A student who meets the standard on every criterion, which is the goal the rubric sets, finishes with a 75%.
Take one essay scored on four criteria: 3, 2, 2, 3. That is 10 of 16 points, an average level of 2.5 — halfway between Approaching and Meets.
| Method | Percentage | Letter (10-point) |
|---|---|---|
| Linear (10 ÷ 16) | 62.5% | D |
| Floor scale, 50% floor | 75% | C |
| Example table (2.5 → 77) | 77% | C |
Same work, same rubric, a letter grade apart. None of these is “the correct” answer, but only the linear one treats a rubric as if it were a test.
The floor scale
A floor scale keeps the even spacing between levels but moves the bottom up. You choose the percentage the lowest level is worth; the top level is 100% and every step between is equal:
% = floor + (average − lowest level) ÷ (top level − lowest level) × (100 − floor)
With a 50% floor on a 1–4 rubric, the levels become 50%, 66.7%, 83.3% and 100%. Meets on everything is a B; Beginning on everything is still an F. Raise the floor to 60% and Beginning becomes a D.
Its strength is that it is one number you can state in a sentence, and it keeps the rubric's equal spacing. Its weakness is that the floor applies to whatever your lowest level is. If you allow a 0 for no evidence, the 0 receives the floor, so decide whether missing work belongs on the rubric at all or is recorded separately.
Conversion tables
A table maps the average rubric score directly to a percentage. The calculator starts with an example — 4.0 → 100, 3.5 → 95, 3.0 → 85, 2.5 → 77, 2.0 → 70, 1.5 → 65, 1.0 → 60 — which you should replace with your own. A table lets a school decide outright that Meets is a B and that the lowest passing level is a D, rather than having those outcomes fall out of arithmetic.
Choose how averages between rows are handled. Step gives an average of 2.9 the 2.5 row, 77%, while 3.0 gets 85% — an eight-point jump for a tenth of a level. Interpolate draws a line between rows, so 2.9 becomes 83.4%. Stepping matches a printed table exactly; interpolating removes the cliffs that generate grade disputes. The cost of any table is that someone has to write the numbers and defend them.
Standards-based grading in a traditional gradebook
If you grade by standards but your school's gradebook only accepts points or percentages, the conversion happens somewhere whether you choose it or not. Entering “3 out of 4” lets the gradebook apply the linear method for you. Converting first and entering the percentage out of 100 puts the method under your control.
- Keep the rubric levels on the feedback students see; the percentage is for the gradebook.
- Use one method per category. Mixing linearly converted rubrics with floor-converted ones in the same average puts students on different scales.
- If some criteria matter more — content over formatting, say — weight them here rather than adjusting the final percentage by hand.
Choosing a method students and parents will see as fair
Start with whatever your school or department already publishes. If there is a conversion table, enter it and use it. If there isn't, open the conversion chart for your rubric and answer two questions: what should a student who meets the standard on every criterion earn, and what should consistent Beginning work earn? Pick the method — and the floor or table — whose answers you would defend at a parent conference.
Then decide before grading, write it on the rubric or in the syllabus, and apply it to the whole class for the term. When you hand work back, show both the levels and the converted percentage so the link between them is visible. For right-or-wrong tests rather than rubrics, the easy grader gives a score chart by number of wrong answers.
Frequently asked questions
How do I convert a 4-point rubric score to a percentage?
The straight method divides points earned by points possible, so 3 out of 4 is 75% and 2 out of 4 is 50%. Because that makes 'Meets' a C and 'Approaching' an F, many teachers instead use a floor scale (the lowest level maps to a set floor such as 50%, the top level to 100%) or a conversion table that maps each average rubric score to a percentage.
Why is 2 out of 4 on a rubric not 50%?
Arithmetically it is, but rubric levels describe quality of work, not the share of questions answered correctly. A 2 usually means 'approaching the standard' — partial understanding — which most teachers would not put in the same band as missing work. Linear conversion places three of the four levels at 75% or below, so it grades harder than the rubric's own descriptions.
What is a floor scale for rubrics?
It assigns the lowest rubric level a minimum percentage — the floor — and the top level 100%, with equal steps between. With a 50% floor on a 1–4 rubric, 1 = 50%, 2 = 66.7%, 3 = 83.3% and 4 = 100%. You choose the floor; the calculator shows the result for any value.
Should I interpolate or step my conversion table?
Step gives every average the percentage of the highest row it reaches, so 2.9 gets the 2.5 row. That is simple to explain but creates a jump at each row. Interpolate draws a straight line between rows, so 2.9 lands most of the way to the 3.0 row. Interpolation avoids cliffs; stepping matches a printed table exactly.
Can I weight some criteria more than others?
Yes. Turn on 'Weight criteria differently' and give each criterion a relative weight. A criterion weighted 2 counts twice as much as one weighted 1 in the average level and in every conversion.
How do I get the results into my gradebook?
Use Whole class mode, type each student's levels, then press Copy results. It copies tab-separated columns — name, total, possible, percent and letter — which paste into a spreadsheet and into most gradebooks that accept pasted or imported columns.
Are my students' scores stored anywhere?
Only in your own browser. The rubric, the class grid and any saved rubrics are kept in this browser's local storage and never sent to a server. Clearing your browser data removes them.