Beware of free wind load calculators. You should be sure that the wind load calculations are correct, and if you have questions are able to discuss and review the wind load pressure output if necessary. When using a free online wind load calculator you are at (high) risk of it being outdated, or having other problems.
Windloadcalc.com is the best solution, as we have been in the wind load business since 2001 and are one of the pioneers of wind loads online. If you need wind load pressures, be sure you have someone that can be trusted and with a company that cares about its customers.