Why the question has no single answer
People want a cutoff, and there is not one. A score that gets you admitted to one school will be below the median at another. Instead of chasing a number someone on the internet called good, work backward from the colleges you actually want.
We are not going to quote percentile numbers here. Percentile tables change every year and there are several different ones, including a nationally representative sample and an SAT user sample, which give different results for the same score. Look up the current official table on College Board's site rather than trusting a number in a blog post.
The graph of the quadratic function f is shown in the xy-plane. What is the y-coordinate of the vertex of the graph?
The one number to look up
Every college in the United States publishes a Common Data Set, and section C9 of it lists the 25th and 75th percentile SAT scores of the students they enrolled. That range is the honest answer to whether your score is good for that school.
If your score is at or above the 75th percentile of a school's enrolled students, the test is helping your application. If it is below the 25th percentile, the test is a weak point. In between, it is roughly neutral and the rest of your application carries the decision.
Search for the college name plus common data set, or plus class profile. Both work, and both come from the school itself rather than from a ranking site.
Test optional changes the question
Many colleges do not require a score. At those schools, the question is not whether your score is good but whether submitting it helps you. The usual rule of thumb is to submit if you are at or above the school's median, and to consider withholding if you are well below the 25th percentile.
Some schools have gone back to requiring scores, and policies move year to year. Check each school's admissions page directly for the year you are applying, not a list compiled a while ago.
Good relative to yourself
There is a second, more useful definition of a good score: better than the one you would get without preparing. Take a full official practice test early, get a baseline, and measure everything against that. A 250 point improvement is real progress whether the final number is 1150 or 1500.
Scholarship money is also worth naming here. Plenty of state schools and merit programs publish score thresholds that unlock specific award amounts. Those are actual cutoffs, unlike admissions, and they are usually easy to find on the financial aid page.
How the section scores split
Your total is the sum of two section scores, Reading and Writing from 200 to 800 and Math from 200 to 800. Colleges see both. A lopsided 1400 made of 780 Math and 620 Reading and Writing reads differently at an engineering school than at a liberal arts college.
If you are applying to a quantitative program, the Math section score is the one admissions officers look at closely, so fixing a low Math score tends to be worth more than adding the same number of points on the other side.