How do I know if my PDF has form fields?

Open it in a PDF reader and press Tab. If a cursor jumps into a box, it has form fields. If nothing happens, it is a flat PDF and most merge tools will reject it.

Can I add text to a scanned PDF?

Yes. A scan is just an image inside a PDF page, so text is drawn on top of it. The scan itself is not altered and its text is not made searchable — this places new text, it does not run OCR.

Do I have to create form fields first?

No, and that is the point. Creating fields in Acrobat is the step this skips. You position values visually on the page instead.

Fill a PDF That Has No Form Fields

Place text anywhere on a flat template and generate one document per spreadsheet row — no fillable form required.

You do not need a fillable PDF to fill one. Instead of mapping columns to named form fields, place text visually on the page itself — which works on flat exports, designer files and scans alike — then generate one document per spreadsheet row.

The situation is familiar. You have a PDF from a designer, a printer, or a scanner. You have a spreadsheet. You want one filled-in copy per row. Then the tool you picked asks you to map your columns to the PDF's form fields, and your PDF does not have any.

This is the most common dead end in PDF mail merge, and it is a real technical constraint rather than an oversight. Filling a form field is easy: the field already exists, has a name, and knows where it sits. Writing onto a page that has no fields means deciding where the text goes, and that needs a visual editor rather than a mapping table.

Two different jobs that sound identical

Filling form fields	Placing text on a page
Template must be a fillable PDF	Any PDF works
Match column names to field names	Drag a column where you want it
Position and style are fixed by the form	You control position, size, colour
Scans are unusable	Scans work

Neither is better in general. If your template already has clean, well-named form fields, mapping to them is faster and more precise. The problem is that most templates in the real world — certificates, invoices designed in Illustrator, scanned government forms, printed letterheads — never had fields to begin with.

How to check what you have

Open the PDF and press Tab. If the cursor jumps into a box, you have form fields. If nothing happens, the file is flat — and every tool that insists on named fields will turn you away.

Doing it without fields

Load your spreadsheet and your PDF. Nothing is uploaded; both are read in the browser.
Drag each column name onto the page where its value belongs. Adjust font size and colour to match the design. Multi-page templates are fine — place fields on whichever page you need.
Choose the column that should name each output file, then download everything as one ZIP.

It is worth being concrete about which tools hit this wall. Word and LibreOffice both do mail merge well, and LibreOffice will even name output files from a data field — but neither can write onto an existing PDF at all; they merge into a document you build yourself. Acrobat plugins and most bulk-fill utilities take the other route and require named AcroForm fields, which a flat export does not have. Either way the answer is the same: rebuild the template first. That is the step this skips.

Where the files go — fully client-side, never uploaded

Flat PDFs are usually the sensitive ones: signed forms, scanned identity documents, letterheads carrying customer data. Uploading those to a merge service means a processing agreement, a cross-border transfer question, and a vendor to audit.

Nothing is uploaded here. Your PDF and spreadsheet are read by the page, rendered on your machine, and saved back to your disk. That is enforced rather than promised: the page ships a Content-Security-Policy whoseconnect-src is restricted to its own origin, so the application is not able to transmit your files anywhere. Open devtools, run a merge, and watch the network tab stay empty.

Getting the placement right

Positioning text on a page you cannot edit takes a little care, and two habits save most of the rework.

First, place against your longest value, not your shortest. If your name column contains both Ali Kaya and Mehmet Ali Büyükşahin, position and size the field so the long one still fits. Text is drawn at a fixed point rather than fitted into a box, so the short entries will look fine either way — it is the long ones that spill.

Second, generate one document before you generate three hundred. Run the merge, open the first PDF, and check it against the template at full zoom. Adjusting one field after seeing real output beats re-running a large batch because a date sat two millimetres too high.

Honest limits

Because text is drawn rather than typed into a field, it does not reflow: a value much longer than the space you allowed will run past it, so leave room for your longest entry. Scanned pages stay images — this adds text on top, it does not perform OCR on what is underneath. There is no email delivery, and browser memory makes a few hundred rows comfortable and a few thousand rows not.

Questions people ask

How do I know if my PDF has form fields?: Open it in a PDF reader and press Tab. If a cursor jumps into a box, it has form fields. If nothing happens, it is a flat PDF and most merge tools will reject it.
Can I add text to a scanned PDF?: Yes. A scan is just an image inside a PDF page, so text is drawn on top of it. The scan itself is not altered and its text is not made searchable — this places new text, it does not run OCR.
Do I have to create form fields first?: No, and that is the point. Creating fields in Acrobat is the step this skips. You position values visually on the page instead.

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