Standardised Test Score Conversion Calculator

Work out standardised test score conversion instantly with clear inputs, formula shown and shareable results.

About Standardised Test Score Conversion Calculator

Score scaling maps a raw mark onto a fixed reported range so that results are comparable across test forms of differing difficulty. Linear scaling is the simplest mapping; real tests use equating tables that adjust for form difficulty and are not exactly linear.

Formulas

Linear scaling

Scaled = Minimum + (Maximum - Minimum) x Raw score / Raw maximum

Sensitivity

Scale points per raw mark = (Maximum - Minimum) / Raw maximum

Worked example

With the default values below, Standardised Test Score Conversion Calculator returns Scaled score of 680. Change any input above and every figure here is recalculated in your browser.

Inputs used

Raw score: 48
Maximum raw score: 60
Minimum scaled score: 200
Maximum scaled score: 800

Results

Scaled score: 680
Exact scaled score before rounding: 680.00
Raw score as a percentage: 80.00%
Scale points per raw mark: 10.00

Step by step

1Values used
2Linear scaling
3Sensitivity
4Scaled score= 680
5Exact scaled score before rounding= 680.00
6Raw score as a percentage= 80.00
7Scale points per raw mark= 10.00

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why is a minimum score above zero?

So that the scale has no absolute floor that could be interpreted as a total absence of ability, and to discourage comparison of scaled scores as ratios.

Why does one raw mark move the score by so much?

Because the scale range is compressed into relatively few raw marks. On a 60-mark test mapped to 200-800, each raw mark is worth ten scale points.