How much do subject tests help?

I plan on applying ED to Northeastern this fall. Northeastern only requires subject tests from homeschooled students; I am not. However I took the Chemistry subject test and got a 750. I plan on taking Math II in October. I was wondering how much does a 750, a pretty decent score, help college admission where I am not homeschooled?

Also, if I do not get into NU, would a 750 look “good” to other schools that require subject tests?

Usually any score in the 700s helps. The exception is for super selective schools where it is the norm or at least common to have 800s in subject tests. A 750 on chemistry is a 73rd percentile among those who took the chem subject test. I don’t think schools pay much attention to the percentile.