How to Create a Fillable PDF Form for Free

To create a fillable PDF form for free, open your PDF in a form editor, let it detect the blank lines and boxes, add any missing text fields, checkboxes or drop-down lists, and save. Siliph's Create Forms does this in your browser with no account, LibreOffice is a free desktop alternative, and Adobe Acrobat's form tool is a paid feature.

A form saved as a flat PDF forces people to print it, write on it and scan it back, which brings messy handwriting, missing answers and pages that arrive sideways. A fillable PDF fixes that. The person filling it types into boxes, ticks checkboxes and picks from lists in any PDF reader, then saves and sends it back. This guide shows how to turn an existing PDF into a fillable form for free, how to choose the right field for each question, and how to test the form before it goes out.

Key takeaways

A fillable form contains real form fields. A flat form only shows pictures of boxes, so readers have nowhere to type.
Siliph's Create Forms adds text fields, multiline boxes, checkboxes, radio buttons, drop-down lists and signature boxes to any PDF. It is free, needs no account, and builds the form in your browser.
Detect fields turns underscores, dotted lines and empty boxes into fields in one click; scanned forms need OCR PDF first.
LibreOffice can export a document as a fillable PDF with its Create PDF form option (LibreOffice Help).
Always test the finished form in a reader, such as Chrome or Preview, before you send it.

Fillable form or flat form

Open the PDF and click where an answer should go. If a cursor appears and you can type, the form already has fields. If nothing happens, it is flat. Most forms exported from Word or scanned from paper are flat.

Apple's Preview handles both kinds when filling: "Click a field in the form, then type your text", and if a PDF "won't allow you to type directly into the form, you can add a text box instead" (Apple). That workaround is fine for one person filling one form. If you are sending a form to many people, give them real fields, so every answer lands in the right place and nobody has to fiddle with text boxes. To fill in a form yourself, fields or not, use Fill PDF Form; our guide to filling a PDF form on a phone shows the experience from the other side.

Choose the right field for each question

Question type	Field to use	Useful settings
Name, email, date, short answer	Text field	Field is mandatory for required answers
Address, comments, a longer answer	Multiline text	A tall enough box for the expected length
Yes or no, agree to terms	Checkbox	Field is mandatory for consent boxes
One choice from a few options	Radio button	The same Radio group name for every option
One choice from a long list	Drop-down list	Options, one per line; Allow multiple selections if needed
A code, PIN or postcode	Text field	Max length with Divide into boxes, for one box per character
Where someone should sign	Signature box	A clearly marked area; not a certificate signature

Give each field a short, clear Name, such as "first_name" or "start_date". Names matter when you collect answers from many forms, because they label each value in the data.

How to create a fillable PDF form with Siliph

Open Create Forms and click Open a PDF to build a form. The pages load in the editor with a toolbar at the top.
Open Forms and click Detect fields. The editor turns runs of underscores, dotted lines, empty box symbols and gaps after labels such as "Name:" into text fields and checkboxes.
Add anything it missed. Pick Text field, Multiline text, Drop-down list, Radio button, Checkbox or Signature box, and click the page where it belongs. Drag and resize the field to fit the printed box.
Set each field's rules in the dialog that appears: Name, Default value, Options one per line for drop-downs, Radio group, Max length, and the tick boxes for Field is mandatory, Read-only, Divide into boxes and Repeat on all pages.
Choose Change tab order under Forms so the Tab key moves through the fields in reading order.
Click Apply changes, then Download PDF.

Create Forms works in your browser, so the document stays on your device while you add fields. It is free, needs no account and adds no watermark. To adjust a PDF that is already a form, choose Edit existing fields to move, resize, rename or delete its fields. The Create Fillable PDF Form page opens the same editor.

Practical tipDetect fields reads the text on the page. A scanned form is a picture with no text, so detection finds nothing. Run OCR PDF on it first, then open the searchable copy in Create Forms.

Test the form like the person filling it

Before you send the form, open the downloaded file in at least one other reader and fill it in yourself:

Type into every field, including a long answer in each box, to check text does not run out of space.
Press Tab from the top. The cursor should move down the page in order, not jump around.
Click each radio button group. Only one option in a group should stay selected; if two can be ticked at once, they do not share a Radio group name.
Save, close and reopen the filled copy to make sure the answers stay.

Chrome's built-in viewer lets people "Fill out and sign paperwork" and download the result "With your changes" (Chrome Help), so it is a good test for recipients who have no PDF software.

Free and paid alternatives

LibreOffice, on Windows, Mac and Linux

LibreOffice is free and open source. You can build the form in Writer with its form controls, then export the document as PDF and tick Create PDF form in the export options. LibreOffice's help describes that option as: "Choose to create a PDF form. This can be filled out and printed by the user of the PDF document" (LibreOffice Help). It suits people who are designing a new form from scratch rather than converting an existing PDF.

Adobe Acrobat (paid)

In Acrobat, select All tools > Prepare a form and choose a file or a scan. Adobe says "Acrobat automatically identifies static form fields and transforms them into fillable text fields" (Adobe). Adobe's free online editor does not include it: Adobe notes that businesses that need to "create fillable forms" can upgrade to Acrobat Pro (Adobe).

Mac Preview, iPhone and Android

Preview on Mac and iPhone, and the PDF viewers on Android, can fill and sign forms but do not offer tools for creating form fields in the help pages we checked. On any of these devices, open Create Forms in the browser. Placing fields precisely is easier on a computer or tablet than on a small phone screen.

Common problems and fixes

Problem	Fix
Detect fields found nothing	The form is a scan; run OCR PDF first, or place fields by hand
A field sits slightly off the printed line	Drag and resize it; zoom in for precision
Tab jumps around the page	Use Change tab order under Forms
Long answers get cut off	Switch that question to Multiline text and make the box taller
Two radio buttons can both be ticked	Give them the same Radio group name
Recipients' answers disappear	Ask them to save or download the filled copy, not just close the viewer

When completed forms come back, Flatten PDF merges the answers into the page so they cannot be changed, and Merge PDF combines several returned forms into one file. If a form should carry a signature, see our guide on signing a PDF online legally.

Frequently asked questions

How do I make a PDF fillable for free?

Open it in Create Forms, click Detect fields under Forms to turn blank lines and boxes into fields, add any missing fields by hand, then click Apply changes and Download PDF. It is free with no account.

Can people fill in my form without special software?

Yes. The fields are standard PDF form fields, so Adobe Acrobat Reader, macOS Preview and the PDF viewers in Chrome, Edge and Firefox can fill them in.

Can I create a fillable form from a scanned PDF?

Yes, in two steps. Run OCR PDF on the scan so the page has a text layer, then open it in Create Forms and use Detect fields. You can also skip detection and place every field by hand.

Is the Signature box a digital signature?

No. It marks where someone should sign. The signer can add a drawn or typed signature there with Sign PDF or a reader that supports signing. A certificate-based digital signature needs a separate service.

Can I edit the fields of a PDF that is already a form?

Yes. In Create Forms, choose Edit existing fields under Forms to load the current fields, then move, resize, rename or delete them, and use Change tab order to fix the keyboard order.

How to Create a Fillable PDF Form for Free