What is the Selection Index formula?

Double your Reading and Writing section score, add your Math section score, and divide the result by 10. College Board gives the worked example 2(620) plus 500, divided by 10, equals 174.

What is the range of the Selection Index?

48 to 228. The floor comes from the minimum section scores of 160 and 160, and the ceiling from two perfect 760s.

Why is Reading and Writing weighted double?

It is how NMSC has always defined the index. In practice it means a point of Reading and Writing is worth twice as much as a point of Math for National Merit purposes, which is worth knowing if you are deciding where to put your preparation.

What Selection Index qualifies for Semifinalist?

It depends on your state and your graduating class, and NMSC publishes nothing. Cutoffs have historically ranged roughly from the low 210s to the mid 220s across states. Any specific figure you find online is compiled from student and school reports rather than published by NMSC.

Does the PSAT 10 count for National Merit?

No. Only the PSAT/NMSQT, and normally only the one taken in 11th grade.

National Merit Selection Index calculator

Enter your PSAT/NMSQT section scores. The index weights Reading and Writing twice as heavily as Math, which is the thing most people do not expect.

Reading and Writing

160 to 760

Math

160 to 760

Selection Index

NMSC publishes no qualifying cutoffs, for any state or any year. This tool will not tell you whether you qualified, because nobody can tell you that from public data.

The formula, and why the weighting matters

Selection Index = (2 x Reading and Writing + Math) / 10

College Board's own worked example is 2(620) plus 500, divided by 10, giving 174. The index runs from 48 at the floor of both scales to 228 at two perfect 760s.

The double weighting has a practical consequence that surprises people. Ten points of Reading and Writing move your index by two. Ten points of Math move it by one. If you are preparing specifically with National Merit in mind, that ratio is worth knowing before you decide where to spend your time.

It is always a whole number

Section scores only move in steps of 10, so the numerator is always a multiple of 10 and the index always comes out as an integer. If you see a Selection Index with a decimal point, something upstream has gone wrong.

Only the PSAT/NMSQT counts

The Selection Index exists on the PSAT/NMSQT and nowhere else in the suite. PSAT 10 and PSAT 8/9 use the same scoring machinery but have no index, because National Merit does not use them. Normally only the NMSQT taken in 11th grade is the qualifying one.

On cutoffs

NMSC does not publish qualifying Selection Index scores. Not for states, not nationally, not retroactively. Every cutoff table on the internet is assembled from students and schools reporting what they were told, and the most careful of those compilations still describes itself as crowd-sourced.

Cutoffs also move year to year and vary widely by state. Treating last year's figure as this year's threshold is a reliable way to be wrong. The guide covers this in more detail.

To go from raw answers on a practice test to the section scores this calculator needs, use the PSAT score calculator.

Common questions

What is the Selection Index formula?: Double your Reading and Writing section score, add your Math section score, and divide the result by 10. College Board gives the worked example 2(620) plus 500, divided by 10, equals 174.
What is the range of the Selection Index?: 48 to 228. The floor comes from the minimum section scores of 160 and 160, and the ceiling from two perfect 760s.
Why is Reading and Writing weighted double?: It is how NMSC has always defined the index. In practice it means a point of Reading and Writing is worth twice as much as a point of Math for National Merit purposes, which is worth knowing if you are deciding where to put your preparation.
What Selection Index qualifies for Semifinalist?: It depends on your state and your graduating class, and NMSC publishes nothing. Cutoffs have historically ranged roughly from the low 210s to the mid 220s across states. Any specific figure you find online is compiled from student and school reports rather than published by NMSC.
Does the PSAT 10 count for National Merit?: No. Only the PSAT/NMSQT, and normally only the one taken in 11th grade.