Auto-summing possible?

Hi @jessica_0941,

Thank you for reaching out. As you know, this most likely can be achieved with  

To meet your requirement, where the total field should only calculate based on newly entered values and not on pre-existing values, a standard field calculation (sum of fields) would not be sufficient.

You would need to use a custom JavaScript inside the form to control when and how the sum is calculated.

Here’s a basic example of how you could achieve this:

1. Open your form in Adobe Acrobat (Standard or Pro).

2. Go to the Prepare Form and select your fields.

3. Right-click the “Total” field, choose Properties, and go to the Calculate tab.

4. Select Custom Calculation Script, and enter a script similar to this:

// Example script
var f1 = this.getField("Field1");
var f2 = this.getField("Field2");
var f3 = this.getField("Field3");

var sum = 0;

// Check if the field was newly filled (example logic: not pre-populated or modified)
if (!f1.isDefaultValue) sum += Number(f1.value);
if (!f2.isDefaultValue) sum += Number(f2.value);
if (!f3.isDefaultValue) sum += Number(f3.value);

event.value = sum;

Important:

• isDefaultValue helps identify whether a field value has changed since the form was opened.

• You can adjust the logic based on how you distinguish between “existing” and “new” data.

Alternatively, you can add a check box, and based on that, you can decide whether to pay this fee or not. 

For this use the simplified field notation.

Thank you, I don't seem to have a calculate tab in field properties? Only General, Appearance, Position and Options. Can't find any options for calculating at all? I'm using the Creative Cloud Acrobat DC...