PDF form builder: how to create a fillable PDF or an online form that produces one

People who search for a "PDF form builder" usually want one of two quite different things. Some want a fillable PDF: a document with boxes that someone types into before sending it back. Others want an online form that produces a PDF: a web page with questions, where each set of answers becomes its own finished document. Both are useful, but they solve different problems. Knowing which one you need makes it much easier to choose a PDF form builder.

The two meanings of "PDF form"

A simple test: if the page layout is fixed and you only need gaps filled in, a fillable PDF is enough. If you send the same kind of document to client after client, an online form saves the copying.

How to make a fillable PDF

In Adobe Acrobat

Acrobat can turn an existing file into a fillable form. Adobe's own tutorial describes turning "a scanned paper form or document created in InDesign, Microsoft Word, Excel, or other application" into a fillable PDF. In practice, it goes like this:

1. Write the document in your usual program, leaving space where answers go.
2. Open it in Acrobat and start its form tool.
3. Place a field wherever an answer goes, and check each one: text, check box, drop-down list, date and so on. Rename them so you recognise them later.
4. Add calculations if you need them. Adobe's help explains how a field can work out totals from other fields.
5. Save the PDF and send it.

In Microsoft Word

Word has its own forms, built with content controls from the Developer tab. Microsoft's guide lists the steps: show the Developer tab, start from a template or a blank page, add controls (plain text, picture, drop-down list, date picker, check box), set their properties, then use Restrict Editing so people can only fill in the fields. This makes a form that is completed in Word or printed. Microsoft's guide does not cover keeping those fields fillable in a PDF, so if you need a fillable PDF, finish the file in a PDF editor.

In LibreOffice Writer (free)

LibreOffice Writer has form controls too. You place text boxes and check boxes in the document, then export it as a PDF with the Create PDF form option ticked. It costs nothing and works offline, which makes it a reasonable free PDF form builder for simple documents.

The limits of a fillable PDF

• Every person fills in a copy of the file, then has to save it and send it back.
• On a phone, small boxes on an A4 page are hard to tap, and how well a form works depends on the reading app.
• Answers arrive as separate files, so comparing or exporting them is manual.
• If you change the document, the old copies are still out there.

How an online PDF form builder works

A form-to-PDF generator turns the job around. You build the questions once, design the document once, and share a link. Each person who answers gets their own PDF.

This is the approach Fillfold takes. Here is how it works in practice.

1. Start from a template or a blank form. There are 97 ready-made templates, from quotes to inspection reports. You can also describe the form you need and let AI draft it. See starting from a template and drafting a form with AI.
2. Add the questions. Short and long text, dates, choices, yes or no, addresses, amounts of money, image uploads, drawn signatures and more. A question can appear only when an earlier answer calls for it. The full list is in question types.
3. Add totals if the document needs them. A Line items question is a table filled in row by row, and each line total is worked out as quantity times unit price. Calculation questions then give the subtotal, the VAT and the total. See calculations and totals.
4. Design the PDF. Your logo, your colours, your wording, and each answer, photo and total placed where it belongs. See design the PDF. Enter your business details once and print them on every document, so you never retype them.
5. Publish and share one link. Send it, or embed the form on your website. See publish and share.

Your client opens the link on any phone or computer, without an account. They answer, add photos, sign with a finger, and at the end they can open their PDF and save it. Each response also arrives in your account with its PDF.

Which one to choose

A few habits that make any PDF form better

• Ask only what the document needs. Every extra required field loses a few people.
• Write labels as questions. "When was the work completed?" is clearer than "Date".
• Test it on a phone before you send it, because that is where most people will open it.
• Name the file and the document clearly, for example "Quote" with the client's name and a reference.
• Keep a copy of every version you send, whatever the tool.

Start from a ready-made form

If you need a document built from answers rather than a single fillable file, the quickest start is to pick a template and change what does not fit. Browse all 97 templates, or open the quote with totals, the inspection report or the work completion certificate, add your logo, and share the link.