What is the best size for JotForm header art?

Hi, 

I want our designer to put together header art some new forms. What is the best size to ask them to make so it looks good on both web and mobile devices?

Cheers,

Bella

Actually, you can use any size you preferred in the Header of your form. Forms built in JotForm BuilderV4 are mobile responsive-ready so it also looks good on both web and mobile devices.

Let us know if you need further assistance.
Cheers.