How can I validate a field using an external web service?

Hi there

How can i validate a field using an external web service?

I need to put the CPF from Brazil is the same of TAX ID in US, and request that to my webservice to check if the ID is correct, valid and etc...

Also i want to fill up the address based on the information collected at the webservice based on the CPF/TAX ID number

Unfortunately, it is not possible to fetch the data from external sources using JotForm. However, it may be possible by embedding the form using the full source code and add some additional programming code to validate the field. You may hire a programmer from Upwork or Freelancer to achieve your requirement.