Can I visit the USA twice in a year with an ESTA [duplicate]

An ESTA allows you to visit for 90 days maximum in one visit.

Leaving the country ends that visit and will reset the clock when you return and you can therefore return for up to 90 days, unless you went to Canada, Mexico or the Caribbean, which are all counted as not having left and the clock on the original 90 days will still be running. (any time spent in those countries counts as time in the US)

You also cant keep doing it.. the purpose of an ESTA is for occasional travel. Twice should be fine though.

Assuming your passport is valid and you have a visa, or are from a country that participates in the Visa Waiver Program, you should not be denied entry to visit the US.

According to US Customs and Border Protection:

Your ESTA authorization is generally valid for multiple trips over a period of two years (starting the date that you are approved) or until your passport expires, whichever comes first*.

The * refers to:

*If you obtain a new passport or change your name, gender or country of citizenship, you will be required to apply for a new travel authorization. This is also required if one of your answers to any of the VWP eligibility questions changes. The associated fee of $14 will be charged for each new application submitted.