What this calculator does
This tool averages whole-number school marks — the kind used on a 2–5, 1–5, 1–10 or 1–12 scale, or any custom range you set. Type in your marks, give some of them a weight if they count for more than others, and the calculator returns the exact average, the average rounded to two decimal places, and a whole mark worked out by a rounding rule you choose. It can also tell you how many more top marks you would need to reach an average you are aiming for. It does not work with percentages or letter grades (A, B, C) — for that, use the separate https://easycalculatorsmart.com/grade-calculator/ page. If you only need a plain arithmetic mean of any numbers, the https://easycalculatorsmart.com/average-calculator/ is the general-purpose version.
Every number is worked out with exact fractions, not floating-point decimals, so 21 ÷ 5 always shows as 4.2 — never 4.199999999999999.
Entering your marks
Add one row per mark, or paste several at once into the quick-entry
box, separated by spaces — for example 5 4 5 3 4. Each
mark must be a whole number inside the scale you picked: on a 1–10
scale, marks below 1 or above 10 are rejected. Decimal marks such as
4.5 are not accepted, because a mark is something a teacher gives,
not a result you calculate.
Next to each mark is an optional weight. Leave it blank and the weight is 1. A weight can be a whole number or a decimal, but it must be greater than zero — a mark cannot be worth nothing or count backwards. Give an exam a weight of 2 or 3 and it pulls the average toward itself twice or three times as hard as an ordinary mark.
How the average is calculated
With no weights entered, the average is the ordinary arithmetic mean: add up all the marks and divide by how many there are. For the marks 5, 4, 5, 3 and 4, the total is 21 and there are five marks, so the average is 21 ÷ 5 = 4.2.
Weighted average
When marks carry different weights, multiply each mark by its weight, add those products together, and divide by the sum of the weights:
weighted average = Σ(mark × weight) ÷ Σ weight
Σ (sigma) just means "add these up." A 5 with weight 2, a 4 with weight 1 and a 3 with weight 1 give (5 × 2 + 4 × 1 + 3 × 1) ÷ (2 + 1 + 1) = 17 ÷ 4 = 4.25 — higher than the plain average of the same three marks, which is 4, because the 5 counted twice.
From an average to a whole mark
A term or final mark on a report is almost always a whole number, so the exact average has to be rounded somehow — and schools do not all agree on the rule. Ordinary rounding turns an average of 4.5 or higher into 5, and anything below 4.5, such as 4.49, stays at 4. Some schools only round up from 4.6. The calculator lets you set this threshold yourself, either by picking a preset or entering a custom value between 0 and 1, and shows three numbers side by side: the exact average, the average rounded to two decimal places, and the whole mark the threshold gives.
| Marks | Exact average | Threshold 0.5 | Threshold 0.6 |
|---|---|---|---|
| 5, 4, 5, 3, 4 | 4.2 | 4 | 4 |
| 5 (w2), 4, 3 | 4.25 | 4 | 4 |
| average of 4.5 | 4.5 | 5 | 4 |
The last row shows why the threshold matters: an average of exactly 4.5 becomes a 5 under ordinary rounding but stays a 4 once a school requires 4.6. Neither result is more "correct" — the whole mark shown is a calculation under the rule you picked, not an official grade.
How many more top marks you need
Enter a target average and, optionally, the weight each new mark would carry, and the calculator works out the fewest extra top marks that would lift your average to at least that target. If your current marks add up to a weighted sum S with total weight W, then after k more marks of value T and weight w, the new average is (S + T·w·k) ÷ (W + w·k). The calculator finds the smallest whole number k for which this reaches your target.
For example, with 5, 4, 5, 3, 4 on a 2–5 scale (sum 21, weight 5, each new mark a 5 with weight 1), reaching a target of 4.5 takes three more 5s: (21 + 5 × 3) ÷ (5 + 3) = 36 ÷ 8 = 4.5 exactly. Two more 5s would only reach (21 + 10) ÷ 7 ≈ 4.43, still short.
Worked examples
Example 1 — plain average, no weights
Marks: 5, 4, 5, 3, 4 on a 1–10 scale. Sum = 21, count = 5, exact average = 21 ÷ 5 = 4.2. Under a 0.5 rounding threshold, the whole mark is 4, because the fractional part (0.2) is below 0.5.
Example 2 — weighted marks
Marks: a 5 with weight 2 (an exam), a 4 with weight 1 and a 3 with weight 1 (homework). Weighted sum = 5×2 + 4×1 + 3×1 = 17. Total weight = 2 + 1 + 1 = 4. Weighted average = 17 ÷ 4 = 4.25. The same three marks without weights average to 4 — the weighted exam mark raises it by a quarter of a point.
Example 3 — reaching a target
Starting from 5, 4, 5, 3, 4 (average 4.2) and aiming for 4.5 with weight-1 marks of the top value (5), the calculator needs 3 more 5s: the new average is (21 + 15) ÷ 8 = 4.5.
Reading the result
The result panel shows the average mark first, then a bar drawn between the lowest and highest mark on your chosen scale. Below that are the whole mark under your rounding rule, the rounded average, the number of marks, and their sum. A table lists how many times each mark appears, and a step list spells out the sum, the weights and the division that produced the average — useful for checking the calculator's working against your own.
Edge cases and limits
- Blank weight. Leaving the weight field empty is the same as entering 1 — it does not mean zero.
- Zero or negative weight. Not accepted. A weight must be greater than zero.
- Target equal to the top mark. The average can get closer and closer to the top mark by adding more top marks, but it can never actually reach it while any lower mark remains in the list. The calculator reports this instead of hunting for an impossible number of extra marks.
- Target above the top mark. No number of extra marks can reach a target higher than the scale allows, and the calculator says so rather than returning a number.
- Decimal marks. The mark fields only accept whole numbers inside your scale — 4.5 is not a valid mark, since marks are what a teacher assigns, and the average is what gets the decimal.
Common mistakes
- Forgetting to set a weight on an exam or final test, so it quietly counts the same as a single homework mark.
- Assuming every school rounds 4.5 up to 5. Many use a higher threshold, such as 4.6 — check with your teacher before relying on the rounded figure.
- Mixing up the plain average with the weighted one. If any mark has a weight other than 1, the two numbers are different, and the plain average is not the one your school will use.
Limitations
The rounding threshold, the scale and the weights are all things you set — the calculator applies them exactly but does not know your school's actual policy. It does not store marks between visits, apply grade curves, or convert to percentages or letter grades; for those, see the related tools linked on this page.
Frequently asked questions
How do I work out my grade average?
Add up all your marks and divide by how many there are. For 5, 4, 5, 3 and 4 the total is 21 and there are 5 marks, so the average is 21 ÷ 5 = 4.2.
How does a weighted average work?
Multiply each mark by its weight, add those products, and divide by the total of the weights. A 5 with weight 2, a 4 and a 3 give (5 × 2 + 4 + 3) ÷ (2 + 1 + 1) = 17 ÷ 4 = 4.25. A mark with weight 2 counts as much as two ordinary marks.
Is 4.5 rounded up to a 5?
It depends on your school. With ordinary rounding, an average of 4.5 or more becomes a 5. Some schools and teachers only round up from 4.6, and a teacher may take other things into account. The calculator lets you choose the rule, and the rounded result is a calculation, not an official grade.
How many top marks do I need to raise my average?
Enter the average you want. The calculator finds the smallest number of extra top marks that lifts your average to at least that value, and shows the average you would then have. For 5, 4, 5, 3, 4 it takes three more 5s to reach 4.5.
Why can my average never reach exactly 5?
While any mark below 5 remains, adding more 5s moves the average closer and closer to 5 without ever reaching it. The calculator says so instead of giving an impossible number of marks.
What if a weight is left blank?
A blank weight counts as 1. Weights can be whole numbers or decimals, but they must be greater than zero.
Can I use a scale other than 2–5?
Yes. Choose 1–5, 1–10, 1–12 or a custom range. The calculator assumes the highest mark is the best one.