How to fill out a PDF form
Filling in a form that carries your income, your ID number or your address means thinking about where that file goes. Here is how to fill it out on your own device instead.
Fillable vs. flat PDFs
A "fillable" PDF has real form fields built in: text boxes, checkboxes and dropdowns the file itself defines, which is why clicking into one in a PDF reader shows a cursor and a box outline. A "flat" PDF, often an old scanned form, has none of that: the fields are just printed lines and boxes with no way to type into them directly, so filling one out means either printing it or placing text over the image by hand.
In Adobe Acrobat
Acrobat Reader (free) can fill in a form that already has fields, tick its boxes and save the result, which covers most fillable government and business forms. For a flat PDF with no real fields, Acrobat needs the paid Pro tier's Prepare Form tool to add them first.
Printing and scanning back
The older method, printing the PDF, filling it by hand and scanning it back, still works for a flat form but produces a lower-quality result than typed text, and needs both a printer and a scanner (or a phone scanning app) on hand.
Filling a form without uploading it
Stayput's fill PDF form tool opens the document in the browser tab: type into its fields, tick its boxes and choose from its dropdowns if it already has them, or place typed text anywhere on a flat, scanned form that does not. The filled PDF saves straight from the tab, with the original file never uploaded to a server at any point, which matters for a form asking for a Social Security number, a bank account or a signature.
Questions
What is the difference between a fillable and a flat PDF?
A fillable PDF has real form fields built in, so a reader can type directly into it. A flat PDF, often an old scan, is just an image of a form with no fields, so text has to be placed over it by hand instead.
Can I fill out a PDF form for free without uploading it?
Yes, Stayput's fill PDF form tool works on the document in your browser tab and never sends the file to a server.
Can I fill in a scanned form that has no real fields?
Yes, by placing typed text directly onto the page at the right spot, which Stayput's tool supports for forms without built-in fields.
Does filling out a form this way keep my answers editable later?
It depends on whether the form's fields stay live in the saved file or get flattened into the page; check the tool's save option if you need to come back and change an answer.