ACT Composite Score Calculator
The ACT composite score is the single number colleges most often look at, and the rule for it is straightforward: average the four section scores (English, Mathematics, Reading, and Science), then round to the nearest whole number, with a half rounding up. Each section is scored from 1 to 36, and so is the composite. This calculator applies that official rule exactly, showing the raw average and the rounded composite, and it validates that every section score sits within the 1 to 36 range. The optional Writing test is reported separately and does not enter the composite.
ACT composite formula
sum = English + Mathematics + Reading + Science
raw average = sum / 4
composite = round(raw average) to nearest whole number
a .5 fractional part rounds up
Each section ranges from 1 to 36 and counts equally. The composite also ranges from 1 to 36. The optional Writing score is separate and excluded.
Notes
- Only the four multiple-choice sections contribute to the composite.
- Standard rounding applies: .5 and above rounds up.
- The maximum composite is 36, achieved with four section scores of 36.
- Writing, when taken, is reported on its own scale separately.
- For percentile ranks, use ACT's published norms for your test year.
ACT composite: frequently asked questions
How is the ACT composite score calculated?
The ACT composite is the average of the four section scores (English, Mathematics, Reading, and Science), each from 1 to 36, rounded to the nearest whole number. Add the four section scores, divide by four, and round. A fractional part of exactly one-half rounds up.
Which sections count toward the composite?
Only the four multiple-choice sections count: English, Mathematics, Reading, and Science. The optional Writing test is reported separately and does not affect the composite. Each of the four counts equally.
How does rounding work?
The average is rounded to the nearest whole number. If the average ends in .5 or higher it rounds up, and below .5 it rounds down. For example, an average of 27.5 rounds to 28, and 27.25 rounds to 27.
What is the range of ACT scores?
Each section is scored from 1 to 36, and the composite is also from 1 to 36. A composite of 36 is the maximum. This calculator validates that each section score falls within 1 to 36.
Does the calculator predict my percentile?
No. The composite is determined by the official averaging-and-rounding rule, which this calculator applies exactly. Percentile ranks come from ACT's published norm tables for each testing year, so consult ACT's official report for your percentile.
Official sources
- ACT: The ACT test overview.
- ACT: official site.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. The composite is the official average of four section scores, rounded. See our methodology.