The main difference between ESTA and a U.S. tourist visa is that ESTA is an online travel authorization available only to citizens of Visa Waiver Program countries for short visits of up to 90 days, while a tourist visa (B-1/B-2) is available to all nationalities, requires a consular interview, and generally allows longer stays of up to 6 months with more flexibility.

ESTA is a quick online travel authorization for citizens of certain countries that lets you visit the U.S. for up to 90 days, while a tourist visa (B-1/B-2) requires an in-person embassy interview but allows longer visits of up to 6 months and can be valid for many years.

ESTA is a quick online authorization for short visits of up to 90 days, while a tourist visa requires an interview and allows longer visits of up to 6 months.