Most PDF forms can be filled in the browser you already have. Open the file, click into a box, type, then save a copy. That only works when the form was built with fillable fields, though, and a surprising number aren't. Some are scans with nothing to click, and some use an old format called XFA that browsers won't open. Here's how to tell which kind you've got and the free way to finish each one. You can add text anywhere on a flat form with our Add Text to PDF tool, and nothing gets uploaded.
Open it in Chrome, Edge, Firefox or Adobe Acrobat Reader and click where you'd write your name. If a cursor appears inside a box, or the fields light up with a blue or grey tint, the form is fillable. If clicking does nothing, or it selects the printed label instead, it's a flat form.
There's a quicker check if you're not sure. Load the file into our Flatten PDF tool and it reports how many interactive fields it found before you change anything. "No form fields detected" means you're looking at a flat page.
| Form type | What you'll see | How to fill it |
|---|---|---|
| Fillable (AcroForm) | Click a box and a cursor appears | Any modern browser, Preview, Acrobat Reader |
| Dynamic (XFA) | "Please wait..." message instead of the form | Download it and open in Adobe Acrobat Reader or Foxit PDF Reader |
| Flat (digital) | Crisp text, but nothing to click | Place text boxes on top, then flatten |
| Scanned | A photo of paper; text may be slightly crooked | Same as flat. OCR won't make it fillable |
| App | Fillable fields | XFA forms | Flat forms |
|---|---|---|---|
| Chrome | Yes | No | No |
| Microsoft Edge | Yes | Off by default; IT can turn it on | Yes, with its add-text tool |
| Firefox | Yes, since version 83 | Yes, since version 93 | Yes, with its text tool |
| Mac Preview | Yes | No | Yes, with text boxes |
| Adobe Acrobat Reader | Yes | Yes | Yes, with Fill & Sign |
| Foxit PDF Reader | Yes | Yes | Yes, with its Fill & Sign tools |
| ToolAspect Add Text to PDF | Types on top, not into fields | No | Yes, no upload |
Firefox added fillable-field support in version 83 and XFA support in version 93, released in October 2021, so it's the one browser that opens most government XFA forms. Edge's documentation calls XFA a legacy format that isn't supported, though administrators can switch it on with a policy called PDFXFAEnabled.
That last step catches more problems than you'd think. Some fields drop text that's too long, and dates typed in the wrong format can be cleared by the form's own scripts.
That message means the file is an XFA form, sometimes called a dynamic PDF. XFA was Adobe's XML-based form format, and the "Please wait..." text is a placeholder that viewers show when they can't run it. Chrome and Mac Preview don't support XFA, and Edge doesn't by default. The fix is to download the file and open it in Adobe Acrobat Reader, Foxit PDF Reader or Firefox. Opening it in another browser tab won't help, because every Chromium-based browser behaves the same way.
You put text on top of the page instead of into fields. In our Add Text to PDF tool, you click the spot where each answer goes, type, pick a size and color, and download the result. The file stays in your browser the whole time, which matters when the form asks for a Social Security number or bank details.
Getting the text size right is what makes a filled flat form look neat. PDF measures in points, and there are 72 points in an inch. A comfortable rule is to make your text about 60% of the box's height:
| Box height on the printed form | In points | Text size that fits |
|---|---|---|
| 3/16 inch (tight table rows) | 13.5 pt | 8 pt |
| 1/4 inch (most form lines) | 18 pt | 10 to 11 pt |
| 5/16 inch | 22.5 pt | 13 to 14 pt |
| 3/8 inch (roomy boxes) | 27 pt | 16 pt |
| 1/2 inch (signature lines) | 36 pt | Use a signature, not text |
When you've added everything, add a signature with Sign PDF if the form needs one.
Usually, yes. A filled form still holds live fields, so anyone who opens it can change your answers. Some upload portals also reject forms with active fields, or show them blank because they only read the page drawing. Flattening bakes the values into the page so they're part of the document. Our Flatten PDF tool has a Forms mode that does exactly this, in your browser.
Keep an unflattened copy, though. Flattening is one-way, and if you spot a typo later it's much easier to fix the fillable version and flatten again. The flattening guide goes into when each mode makes sense.
In the US, generally yes. The federal ESIGN Act of 2000 gives electronic signatures the same legal effect as handwritten ones for most transactions, and nearly every state has adopted the UETA, which says much the same thing. There are exceptions, such as wills and some court documents, and an organization can still insist on ink. If a form says "wet signature required", print it, sign it and scan it back. Our guide to signing a PDF online covers the options.
If the form has fillable fields, open it in Chrome, Edge, Firefox or Mac Preview, click each box and type, then save a copy from the PDF toolbar. If it has no fields, place text on top of the page with a free tool like ToolAspect's Add Text to PDF, which runs in your browser without uploading the file.
Either the form has no fillable fields, or it's an XFA form your viewer can't run. If clicking a box does nothing, it's a flat form, so add text boxes on top. If you see a "Please wait..." message, download the file and open it in Adobe Acrobat Reader, Foxit PDF Reader or Firefox.
Click the download icon in the PDF toolbar at the top right of the viewer and choose a new filename. Chrome saves a copy with your entries in the fields. Reopen the saved file to check the answers are there before you send it.
No. Chrome's built-in viewer doesn't support XFA forms and shows a "Please wait..." placeholder instead. Firefox has supported XFA since version 93, and Adobe Acrobat Reader and Foxit PDF Reader both fill XFA forms for free.
Flatten it before you send it if you don't want anyone to edit your answers, or if an upload portal shows the fields blank. Keep an unflattened copy too, because flattening can't be undone and the fillable version is easier to correct.