How the calculator works out your scores

Every figure the calculator displays comes from documents published by ACT. No figure is estimated from forum posts, and no results are averaged across old tests.

Converting raw scores to scale scores

For the Enhanced ACT, the conversion table for scale scores from ACT's practice test scoring key online (document JA04037.CJ20252) is what the calculator uses. The conversion table covers the form's scored questions. Its raw score limits are 40 for English, 41 for Math, 27 for Reading and 34 for Science.

For the legacy ACT, the calculator uses the Form 2176CPRE conversion table found in Preparing for the ACT 2024–2025. Each scale score in that table comes with a range of raw scores printed by ACT, and the calculator reads those ranges the same way.

Because ACT adjusts the table for each test form, a section result on a real test can come out about a point higher or lower.

The composite score and the rounding rule

With the Enhanced ACT, the composite score is the average across English, Math and Reading. With the legacy ACT, the composite is the average across all four sections. As Understanding Your ACT Scores explains, ACT takes the average and rounds it to the closest whole number. One-half or more goes up, while anything less goes down.

You can check the arithmetic yourself because the calculator shows the sum, then the division, then the rounding step under the composite.

The STEM score and percentiles

The percentiles come from ACT National Ranks for 2026–27. They show what share of recent graduates received a score at or below each one. On the Enhanced ACT, entering Science also makes the calculator show the STEM score. It comes from averaging Math and Science, then rounding, and it has its own rank.

The same rounding applies to a superscore. According to ACT's superscore FAQs, add your highest score in each of English, Math and Reading, then divide by 3.

When tables change

New national ranks from ACT come out once a year. Every September, the ranks and conversion tables get checked against ACT's site, and again whenever ACT makes a new free practice test available. Because the tables sit within the page itself, the calculator never has to wait on another server.

Checks made before each update

Before each update, test cases cover perfect and zero scores, plus the Science and STEM lines. They also check the legacy ACT half-point case, where rounding 27.5 gives 28. Each shipped table is also compared line by line with copies taken from ACT's documents.