**tjaardheikens**Hello,

I would like to add calculations to a field.

1 If two persons are booking a trip then the subtotal price should 2 * the price for a single person

2 A field for calculate the total price of a trip which is the price for the trip and some aditional costs.

How can I calculate in Jotform to make this work?

Best regards,

Tjaard

**moonzkie**Hi,

You can make this possible by adding

**Purchase Order**field on your form. This will allow you to add products and do calculations without prompting your customers to pay online.Hope this helps. Thank you.