How Long Does It Take for a US Visa Online Approval?
https://www.online-usa-visa.org/how-long-does-it-take-for-a-us-visa-online-approval
ESTA applications are processed online, with approval granted almost immediately after submission. However, there are instances where the evaluation of an application may take up to 72 hours. Once a decision has been reached, the applicant will receive an email notification confirming the approval of their ESTA application.