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Grade curve

Paste names and marks, or upload a CSV, and the tool shows the shape of the class first: the count, mean, median, standard deviation, the range, and a histogram of the raw marks.

Then curve, your way: by standard-deviation bands, by percentile quotas, or by a linear scale-up, with the cutoffs editable and the working shown. Curving is a policy choice, not a formula, so this shows the math and leaves the decision with you. Nothing is uploaded.

One a line, as "Name, Mark", or just a column of marks. A header row is ignored.

Paste or upload some marks and the distribution appears here.

Curving is a policy choice, not a formula, and no method here is "the correct" one. Standard-deviation bands, percentile quotas and a linear scale-up give different results by design. Follow your institution's rules, and use this to see and check the maths. The list is read in your browser and never uploaded.

Questions

Is my class data sent anywhere?
No. Every tool here runs in the page itself. There is no server that receives your students' names or their marks, and you can check it in your browser's network tab: using a tool produces no request carrying what you typed. The one thing this site stores is an email address, given at the point you download or copy a result.
Which curve is the correct one?
There is no single correct curve, and any tool that says otherwise is hiding a choice. Standard-deviation bands grade by how far above or below the class mean each mark is. Percentile quotas fix in advance what share get each grade. A linear scale-up gently lifts everyone. Your institution's policy decides which is allowed; this tool shows you what each does so you can check it and defend it.
What do the statistics mean for my class?
The mean and median tell you where the middle sits and whether it is skewed; the standard deviation tells you how spread out the marks are. The histogram shows the actual shape, which is the thing a single number hides. Look at it before you curve, because a curve that suits a bell does odd things to a lopsided class.
Can I adjust the cutoffs?
Yes, and that is the point. The z-score band edges and the percentile shares are editable, and the results table and the count in each grade recompute as you change them, so you can see exactly who moves and settle on cutoffs you can stand behind.
Where does the uploaded list go?
Nowhere. The CSV is read in your browser and the marks are curved on your own device. No student name or mark is sent to a server of ours, which you can confirm in the network tab.

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