How is the 90-day Vietnam visa validity calculated — from the issue date or the start date?

When filling out the immigration form: if the visa issue date is July 29 and the end date entered is November 16, the system throws an error saying the visa can't exceed 90 days (the gap is too long).

One traveler confirmed with their own case: entered August 17 as the start date in the form, and the visa's expiry date came out as November 14 — exactly 90 days from August 17.

A traveler was advised that typically the visa issue date and the start-of-validity date are the same day, so there shouldn't be a discrepancy unless the visa hasn't been physically issued yet.

When completing step 2 (trip information) on the visa application site, the system requires you to enter the visa expiry date before letting you proceed — this is a common sticking point during self-service applications.

Travelers generally advise simply entering the visa's start-of-validity date (same as the issue date) in the form, without trying to calculate anything separately.

A traveler asked where to actually find the visa issue date — it's usually printed on the visa document/sticker itself, issued after the application is approved.