What TOEFL score do you need for RISD?

Both pages say RISD accepts TOEFL MyBest and the TOEFL Home Edition. The graduate FAQ adds that MyBest scoring is accepted for exams taken within one year of each other. It may take three weeks for TOEFL scores to be sent to RISD by the test agency, so plan the test well before the deadline.

The rule covers everyone who speaks English as a second language, US citizens included, and you can meet it with TOEFL, IELTS or Duolingo.

For comparison, the same pages set IELTS at 7.

First-year applicants may use SAT Reading and Writing of 600 or ACT English and Reading of 25 instead. The test can be waived for first-year applicants whose secondary school taught in English, with three consecutive full-time years without ESL, ELL or ENL courses; a waiver form is in the applicant portal. Graduate applicants who studied in English should contact Admissions, and the FAQ says waivers are granted sparingly.

Requirements vary by programme and change between admissions cycles. The score that binds you is the one on your RISD programme page and in your offer letter, so check it there before you book a test.