https://travel.state.gov/content/tra...formation.html

What kinds of tests meet the testing requirement?
Travelers must show documentation of a negative viral COVID-19 test result or documentation of recovery from COVID-19 within the past 90 days before boarding a plane to the United States (or before boarding the first flight in a series of connections booked on the same itinerary to the United States).
Both nucleic acid amplification tests (NAATs), such as a PCR test, and antigen tests qualify.
A self-test can be used if it meets the requirements of the order including real-time proctoring by a telehealth service affiliated with the manufacturer of the test and that generates a test result that can be reviewed by the airline before boarding.   
This is the same standard for qualifying tests that has applied to the pre-departure testing requirement since January.