The College Board and ACT, providers of the SAT and ACT exams respectively, have developed and updated concordance tables "to help the education community better understand how students of comparable ability will score on the two tests."
The comments on both the pages above go into lengthy detail about the limitations of the concordance tables so they are clearly not exact instruments. Still the tables should give advisers and applicants alike an idea of how students who have taken one test will do on the other test.
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