Fill out a PDF form

How does this tool fill a PDF form?

It reads the interactive fields stored in the PDF and shows them as a normal web form with large inputs, grouped by page and ordered top to bottom. Filling a form by clicking tiny boxes on a zoomed-out page is fiddly, especially on a phone. Labels are taken from the field names, and a thumbnail of each page, rendered with pdf.js, helps you match questions to the layout.

When you save, every answer is written back into the original fields and their visual appearance is regenerated, so the values show up in Adobe Acrobat, Preview, browsers and mobile PDF apps alike. The file keeps its structure, so a recipient who processes the form automatically can still read each field by name, provided you leave the flatten option unticked.

Which form field types are supported?

All standard AcroForm field types that hold a value are supported: text fields, checkboxes, radio groups, dropdowns and list boxes. AcroForm is the interactive form model defined in the PDF specification, ISO 32000-2, and it is what nearly every government, bank and HR form uses. Push buttons are left out, and signature fields are listed for reference but cannot be signed here.

• Single-line and multi-line text fields, including maximum length limits with a character counter.
• Checkboxes and radio button groups, with a clear option for radios.
• Dropdowns, including editable combo boxes where you can type your own value.
• List boxes that allow one or several selections.
• Read-only fields are shown but locked, and required fields are marked with an asterisk.

Should I flatten the form after filling it?

Flatten when you are sending a final version, such as a completed application, and want the answers to look the same in every PDF reader. Flattening merges the field values into the page content and removes the fields, so nobody can change an answer afterwards in a normal viewer. Some phone and browser viewers do not draw field values at all, and flattening fixes that too.

Leave the form unflattened if it goes to another person who still has to add information, or if the organisation receiving it extracts field data automatically, because flattening deletes the fields their software reads. When in doubt, save the editable version first. A copy can always be locked later with Flatten PDF, whereas a flattened form cannot be made fillable again.

What if the PDF form has no fillable fields?

Use Edit PDF to type text boxes, check marks and dates directly onto the lines, because a form without fields has nothing for this tool to list. Forms made in a word processor and printed to PDF, and scanned paper forms, look fillable but contain no fields. Sign PDF then adds a signature. Detecting and creating fields automatically is not supported.

How do I avoid mistakes when filling a PDF form?

Work through the form page by page and compare each group of inputs with its page thumbnail, because field names chosen by the form's author are not always clear. Dates and amounts are stored exactly as typed, so follow the format printed on the form, such as DD/MM/YYYY. If a dropdown lists export codes instead of readable choices, pick the one that matches the printed options.

After downloading, open the file in your usual PDF reader and check that every answer appears where you expect before submitting it. Calculated totals and validation scripts inside a form do not run here, so fill in any totals by hand. Password-protected forms ask for the password first, and it is used only on your device to open the file.