How to turn a flat PDF into a fillable form

A sign-up sheet printed, filled in by hand, scanned back and retyped by a volunteer is a lot of people’s idea of a form. A fillable PDF replaces all of that: the same page, with real boxes that people type into and email back. Making one is not hard, but the difference between a form people finish and one they abandon comes down to a few decisions made before you place the first box.

Is a PDF form the right answer?

A fillable PDF suits a fixed document that people should complete and keep: a consent form, an application, an expense claim, a tenancy checklist. It keeps the layout exactly as designed, prints well, and can be saved with the answers inside.

It is a poor fit when you want answers collected in one place automatically, when many people will fill it in on a phone, or when the questions change depending on earlier answers. An online survey does those jobs better. If you are unsure, ask how you will receive the answers. If the honest answer is “by email, one at a time”, a PDF form is fine.

Prepare the page

• Design the page for typing, not handwriting. People need more room than a printed line gives them, particularly for addresses and comments. Leave generous gaps between rows.
• Use one column where you can. The Tab key moves in reading order, and a single column keeps that order predictable.
• Print the labels, not the boxes. If the labels and the boxes are part of the page, you will be placing fields over printed rectangles. Either design the page with labels only and place fields beside them, or place each field exactly over its printed box.
• Save the source as a PDF from your word processor or design program, at the page size people will print.

Plan the fields

Write the list before you place anything. For each question decide the kind of field:

Give each field a short, unique name before you start, such as full_name, email and start_date. Names are how the answers are identified if you ever pull them out in bulk, and how assistive technology refers to each box. Two fields with the same name would share one answer, so keep them distinct. Radio buttons are the exception: all the buttons for one question share a group name, and each has its own value.

Build it

1. Open the PDF in Create a form.
2. Choose a field type, then click the page to drop a field at its default size, or drag to draw the size you want.
3. With a field selected, set its name, tick Required if an answer is needed, add a hover hint, set a longest answer if there is a natural limit, and enter the choices for drop-downs and lists.
4. Fix any field outlined in red. The usual causes are an empty or duplicate name, two radio buttons with the same value, or a drop-down with no choices.
5. Press Create fillable PDF and download the new file. Your original is not changed.

If the PDF already has some fields, they are kept and shown with a dashed outline, and new names are chosen so they never clash. A file with a digital signature will lose it, because adding fields rewrites the file, so you are warned first.

Make it easy to fill in

• Size the boxes for the answer. A text box that is too small hides long answers. Draw an address field tall.
• Add hints where a label is not enough. “Your full name as on your passport” is the sort of hover hint that prevents rejected forms, and readers can expose it to assistive technology as the field’s description.
• Mark what is required, and say so on the page as well, because not every reader highlights required fields the same way.
• Choose date formats to suit your readers. The default is day/month/year; month/day/year and year-month-day are available.
• Keep the order sensible. Tab order is set to rows, left to right then down. Check it matches the order you want people to answer in.

Test before you send it

1. Open the finished file in more than one reader, including a web browser.
2. Click the first box, type, and press Tab all the way through.
3. Tick each check box, choose each radio option and open each drop-down.
4. Enter a date and see that it turns into the format you set.
5. Save the filled copy, close it, reopen it and check the answers are still there.
6. Print it. A form that works on screen but prints with clipped answers is not finished.
7. Try it on a phone if many people will.

Sending it out and getting answers back

Email the file, or put it on a web page for download, with one sentence of instruction: “Fill this in on your computer, save it, and email it back to this address.” This site never sees the form or the answers, so nothing is collected for you; they arrive in your inbox as saved files.

Think about what you are asking for. People will email back whatever you request, including things that should not travel as an ordinary attachment. If the form collects sensitive details, say how they should be sent, or ask for them another way. When a filled form comes back, Flatten PDF fixes the answers into the page so your records cannot be altered by accident, and Protect PDF can lock a copy you keep. To fill in a form yourself rather than build one, use Edit & fill.

Common mistakes

• Reusing a name. Two fields called “Text1” share one answer.
• Placing a box beside the printed line, not over it, so the form shows two boxes.
• Radio buttons with different group names, so people can tick more than one.
• A drop-down with one dummy choice, because the options were never typed in.
• Forgetting the test. One run through with the Tab key finds most problems.
• Sending an editable form when you wanted a record. Flatten the returned copies.