An F-1 visa for students in the United States is typically valid for the duration of the student’s academic program, plus an additional grace period. Here are some key points regarding the validity period of an F-1 visa:

1. Duration of Status (D/S): When an international student enters the United States with an F-1 visa, they are admitted for “Duration of Status” (D/S), which means they are allowed to stay in the country for the duration of their academic program. This includes the period of time required to complete their studies, as indicated on their Form I-20 (Certificate of Eligibility for Nonimmigrant Student Status), as well as any authorized practical training periods following their studies.
2. Grace Period: After completing their academic program or any authorized practical training, F-1 visa holders are granted a grace period of 60 days to depart from the United States. During this time, they can prepare to leave the country, apply for a change of status, or transfer to another academic program or institution.
3. Visa Expiration Date: While the F-1 visa itself may have an expiration date, it does not necessarily dictate how long the student can stay in the United States. The visa expiration date simply indicates the last day on which the student can use the visa to enter the country. Once inside the U.S., the student’s authorized stay is determined by the D/S notation on their Form I-94 (Arrival/Departure Record).
4. Travel Restrictions: Students with an expired F-1 visa can remain in the United States as long as they maintain their status and have a valid Form I-20. However, if they travel abroad and their visa has expired, they will need to obtain a new F-1 visa at a U.S. embassy or consulate before re-entering the country.

Overall, the validity of an F-1 visa is closely tied to the student’s academic program and status in the United States, rather than a fixed expiration date on the visa itself.