Does John Hopkins accept duolingo for its MPH programs?

Yes, Indian students can apply with a Duolingo English Test (DET). This would require a minimum GPA of 110. 

Other than DET, these applicants can also go for the English tests like IELTS, PTE and TOEFL too. Look at the minimum scores required - 

• IELTS with a band of 6.5+ overall (with no sec

No, an invalid or uncertified test result does not count toward your 3 attempt limit. This limit only applies to completed and submitted DET tests. You can book a retake immediately after receiving an invalidation notice without penalty

You must wait for your official DET results. Or an invalidation notice before booking a new slot. It takes 48 hours.

If your test was uncertified due to technical errors, you can book a retake immediately without it counting toward your limit.

You can complete the test up to 3 times within any rolling 30 day period. This limit applies to completed attempts.

DET system will block your payment, if you try to purchase a fourth test within this window.

No EUR University doesn't accept DET it only accepts TOEFL iBT, Cambridge CI Advanced, Cambridge C2 or Academic IELTSOpens external Test Score Reports. Students can refer to official university website for course specific English requirements.