If you've ever glanced through any of the year-end College Board data reports, you may have seen information about the SAT standard deviation. Unfortunately, the reports just list the numbers and then move on, without explaining at all what these numbers mean.
So how is info about the SAT mean and standard deviation useful to you? In this article, we'll explain what the term standard deviation refers to and what it means for you and your SAT score.
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What Is the SAT Standard Deviation?
The standard deviation of a set of numbers measures variability. Standard deviation tells you, on average, how far off most people's scores were from the average (or mean) score. The SAT standard deviation is 217 points, which means that most people scored within 217 points of the mean score on either side (either above or below it).
SAT standard deviation is calculated so that 68% of students score within one standard deviation of the mean, 95% of students score within two standard deviations of the mean, and 99+% of students score within three standard deviations of the mean.
If the standard deviation of a set of scores is low, that means most students get close to the average score (in this case, 1060). This is pretty clearly not the case with the SAT, because otherwise schools that boast 1300+ average SAT scores for admitted students would have no students.
By contrast, if the standard deviation is high, then there's more variability and more students score farther away from the mean. Based on the most recent data released for the SAT, the standard deviation is relatively high, meaning that there is quite a bit of variability in how students score on the SAT.
Below, we've created a table with the data about the SAT mean and standard deviation for each section of the test, as well as the mean and standard deviation for total SAT scores.
SAT Participation and Performance
Note: this table only includes data drawn from the most recent test scores of 2020 high school graduates.
What Does the SAT Bell Curve Look Like?
The bell curve for SAT scores is pretty close to an ideal normal curve. Since the average score is higher than the midpoint of the range (1060 instead of 1000), it's a little shifted over to the right, but otherwise the SAT bell curve is a regular bell shape.
Because the SAT standard deviation for total SAT scores is 217 and the mean is 1060, we can do a little quick math to figure out the score ranges for the first, second, and third standard deviation.
% of SAT scores in range
Total Score Range
To help you better visualize the distribution of SAT scores, we've graphed out the SAT bell curve (in blue) for composite SAT scores (out of 1600) and added in lines for the mean and each of the standard deviations. The green line in the chart is the average SAT score (1060), while the lines on either side of the mean represent the boundaries of the different standard deviations.
The two yellow vertical lines on the chart represent the first standard deviation scores, 843 and 1277. The scores of 68% of all students who took the SAT fall in between those two lines.
The two orange lines on the chart represent the second standard deviation scores, 626 and 1494. The scores of 95% of all students who took the SAT fall in between the two orange lines (including the 68% who scored between an 843 and a 1277).
The two red lines on the chart represent the third standard deviation scores, 409 and 1711. Technically, because the SAT only goes up to 1600, there are no students who scored above that, which is why the blue curve of all student SAT scores stops abruptly at 1600. The scores of about 99% of all students who took the SAT fall between the two red lines, with the remaining <1% falling below the leftmost red line (scores of 409 and below).
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Why Does the SAT Standard Deviation Matter?
As a student, the exact details of the SAT bell curve and standard deviation aren't going to be all that relevant.
Most of the info you'd get from standard deviations you can just as easily get from the information about your percentile rank that's included on your score report. For instance, knowing you're in the 98th percentile is probably more useful to you than knowing you're a little more than two standard deviations above the mean SAT score.
Learn How Much Scores Vary
The size of the standard deviation can give you information about how widely students' scores varied from the average. A larger standard deviation means there was more variation of scores among people who took the test, while a smaller standard deviation means there was less variance.
As we discussed above, the SAT standard deviation is 217, which is relatively high and therefore indicates there's a lot of variation in scores among students who take the SAT.
Practically speaking, this means that high-achieving students have to get relatively high scores in order to distinguish themselves. To do better than 98% of students on the SAT with a mean of 1060 and a standard deviation of 217, you must get a 1490 or higher on the test.
Discover How Your Score Stacks Up
The standard deviation of SAT scores is also useful information because it gives you a good general idea about how well you performed, compared to other students. Based on which standard deviation you fall into, you can even figure out your rough percentile score (if you don't know it).
If your SAT score is more than one standard deviation above the average SAT score, then you did better than about 84% of students, which puts you in a strong position for most state schools (including the University of Montana, University of Cincinnati, and UT San Antonio) and some private schools (like Pace University, Temple University, and Quinnipiac University).
Similarly, if your score is more than two standard deviations above the mean SAT score, then you did better than around 97% of students, which is great and makes you a strong candidate for more competitive schools like NYU, UMich (Ann Arbor), and even Ivy League schools like UPenn and Brown.
On the other hand, if your score is more than one standard deviation below the mean, you definitely have your work cut out for you if you want to be a competitive applicant for most schools. You'll need to put in some serious study time to boost your score up to an 840+ score level.
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Ready to get more precise information of how your SAT score compares to other students' scores? Check out our article on SAT scores and percentiles to figure out where you fit in.
Are you a high-achieving student with high SAT score dreams? Learn what SAT scores you need to get into the Ivy League here.
What if you're worried your score might be too low to get you into college at all? Find out what the minimum SAT score for college is here.
Need to figure out what SAT score to aim for in the first place? We have a complete guide to setting your target SAT score in this article.
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Laura graduated magna cum laude from Wellesley College with a BA in Music and Psychology, and earned a Master's degree in Composition from the Longy School of Music of Bard College. She scored 99 percentile scores on the SAT and GRE and loves advising students on how to excel in high school.