Guides

How to Fill In and Create PDF Forms

To fill a PDF form, open it in Monstera PDF Editor, click a field and type, then save. To make a form, choose Forms and add text fields, tick boxes, dropdowns, date and signature fields, or let Detect find the blanks on a flat form for you. It is free, runs on your PC, and adds no watermark.

  • Fill and build
  • Detects blanks
  • No watermark
The Forms tools show every field of a grant application, with the selected Submit button's options and its submit action in the Properties panel.
Every field of a grant application, with the selected button's options in the Properties panel.

Fillable form or flat form?

A fillable form has real fields: click a box and you can type in it. A flat form is only printed lines and boxes, often a scanned or exported document. Monstera fills the first kind directly, and can turn the second kind into the first.

How to fill in a PDF form in Monstera

  1. Open the form

    Install Monstera free from the Microsoft Store and open the PDF form.

  2. Fill the fields on the page

    Click a text field and type, then press Enter or click elsewhere. Click tick boxes and options to choose them, and click a dropdown or list to pick from it.

  3. Or work from the list

    Open the Forms tab in the document panel to see every field with its kind and page, and fill it in from there. Go to page shows a field on the page.

  4. Save

    Save the document to keep what you entered.

Create your own form fields

In the rail, choose Forms, then pick a field in the Fields group: Text field, Tick box, Radio option, Dropdown, List box, Button, Signature or Date. Click the page to add it at its usual size, or drag a box to size it yourself. Double-click a tool to add several in a row, and press Esc to stop.

Each field is named for you. Rename it, change a dropdown's choices or a date's format in the Properties tab.

Turn a flat form into a fillable one

Go to the page and choose Forms, then Detect. Monstera looks for empty ruled lines, boxes, small squares and small circles with words next to them, marks each one, and lists them. Untick anything that is not a place to write, choose Find on all pages if you like, then Add fields. Lines and wide boxes become text fields, small squares tick boxes, and small circles radio buttons. One Ctrl+Z takes them all back.

Good to know

  • Dates have a calendar. Choose the button at the right edge of a date field, or press Alt+Down; you can always type the date instead.
  • Scripts never run. Monstera does not run scripts from documents, to keep your computer safe. A field worked out by a script is marked with { } and does not update by itself; standard sums and formats still work.
  • Start again with Forms, then Reset form. Every field goes back to how the form started, and signatures stay.
  • Finished? Flatten the form so the answers can no longer be changed, or export the form data.

Questions

Can I fill in a PDF form for free?

Yes. Monstera fills text fields, tick boxes, options, dropdowns, lists and dates for free, with no watermark and no account.

Can I make a non-fillable PDF fillable?

Yes. Forms, then Detect finds the empty lines, boxes and circles on a flat form and turns the ones you keep into real fields. You can also add fields by hand.

What kinds of form fields can I create?

Text fields, tick boxes, radio options, dropdowns, list boxes, buttons, signature fields and date fields.

Why does a calculated field not update?

Monstera never runs scripts from documents, to keep your computer safe, so a field worked out by a script is marked with { } and does not update by itself. Standard sums and formats still work.

Full instructions in the Help

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