Answer piping: Reference previous form answers
Base logic in form fields on previous answers or use them to personalize your form with answer piping.
In many places in Fillout, you may notice a blue (+) button. This lets you reference
- previous form inputs
- URL parameters
- dates (e.g. "today", "a month from now", etc.)
Referencing from the blue (+) buttons
Whenever you see this blue (+), you can reference a previous form input by pressing the button and hitting "Continue" on the page you'd like to reference from:

Then, we can press "Insert" on any of the fields we'd like to reference:

Referencing in field logic
To base show/hide logic for fields on previous form inputs, we can click the "Logic" section on a field and "Set conditional logic." Here, every time we click "Pick reference", the same menu/dropdown as above will be visible. Click here for more details.
Referencing in headings/question labels
To reference previous form inputs in plaintext in the form, we can type "@" in a form field to show the reference menu as above:

Once inserted, you can always hover over the blue tag to see a more full description of what you inserted.