ALL PDF TOOLS37
Fill PDF Form
Fill a PDF Form — Free Online PDF Form Filler
Read a PDF's form fields, type into them, and download the filled copy — flattened or still editable.
About Fill PDF Form
A PDF form is not a picture of a form. Somewhere inside the file is an AcroForm dictionary listing named fields, and this tool reads that list and gives you one control per field: a box to type in for a text field, a tick for a check box, a set of radio buttons for a radio group, a menu for a dropdown, and a multi-select for a list box. Fields the document marks read-only are listed with their stored values and locked. Push buttons, signature fields and anything the engine cannot identify are shown too, each with a line saying why there is nothing there to fill in. Only the fields you actually change are written, and that matters more than it sounds. Writing to a field makes the engine redraw it in a standard Helvetica, keeping its colour, size and alignment but replacing whatever font the document's author picked, so re-sending a value you never edited would restyle a field for nothing. No value you did not touch is altered. When the answers are in, you can also flatten the form. Flattening bakes every field into the page and then removes the fields, which is what people mean by wanting a copy nobody can edit: the text stays real, selectable text rather than turning into a picture, and the result cannot be filled in again. That option is refused for some documents. A field with no stored appearance makes the underlying flatten fail part-way through and leaves a file that will not save at all, so this page names those fields and turns the box off rather than letting you find out afterwards. Filling still works on those documents, and the form stays interactive. Two limits are worth knowing before you start. Field text is drawn with a standard PDF font that covers the Latin alphabet, accented letters, curly quotes, dashes and the euro sign; Chinese, Japanese, Korean, Cyrillic, Greek, Arabic and emoji cannot be encoded at all, so the page checks what you type and stops the run instead of failing halfway through it. And this cannot create a form. A document with lines and boxes drawn on the page has no fields in it, and nothing here adds any — if the form dictionary is missing, your file is handed back untouched. Everything runs in this tab; the PDF is never uploaded.
Questions
Why does this say my PDF has no form fields?
Because it hasn't got any. A PDF form is a list of named fields stored inside the file, and plenty of documents that look exactly like forms are only lines and boxes drawn on the page — a scan of a paper form is the usual case. There is nothing there for any filler to write into. This tool will not add a form dictionary to a document that arrived without one, so your file comes back untouched rather than quietly restructured. If you need writing on that kind of page, what you want is a tool that draws text onto the page, not a form filler.
What does flattening actually do to the form?
It bakes each field's appearance into the page and then deletes the field. The answers stop being editable and stop being form data — the download has no fields left, so nobody can change an answer in a reader and nobody can fill it in again. The text stays real text rather than becoming a picture: on a flattened output the value is drawn with an ordinary text operator and there is no image anywhere in the file, so it still selects, copies and searches. Flattening is not compression — the appearances move into the page rather than going away — and it cannot be undone from the download, so keep the filled, unflattened copy if an answer might change.
Can I type Japanese, Chinese, Cyrillic or emoji into a field?
No, and the page stops you rather than letting the run fail. Form text here is drawn with one of the standard PDF fonts, which can only encode the WinAnsi character set: the Latin alphabet, accented letters, curly quotes, dashes, the euro sign and a handful of typographic marks. Anything outside that makes the library throw while it is saving, with the values already written into the document — so the check happens before the button rather than after it. Answering in those scripts properly needs an embedded Unicode font, which is a font file this site does not ship.
Why can't I edit some of the fields?
Several reasons, and each row says which one applies. A field the document marks read-only is shown with its stored value and locked — worth knowing that the library underneath would overwrite one without complaining, so that lock is this page's doing rather than the format's. A push button holds no value at all. A signature field is not something this tool writes into. A field whose type could not be read from the document's own /FT entry gets no control, because guessing would be worse than saying so. And where two fields share a name, only the first can be written, so the second is locked.
Does this sign a PDF?
No. It fills form fields; it places no signature of any kind, digital or drawn. A signature field in your document is listed so you can see it is there, and nothing is written into it. A signature field is also one of the things that can block flattening: the library never regenerates an appearance for one, so if it arrived without a stored appearance there is nothing for the flatten to bake, and the page turns that option off and names the field instead of failing halfway through.
Is my file uploaded to a server?
No. Transmute processes everything locally in your browser using JavaScript and WebAssembly. Your files never leave your device — there is no server, no upload, no cloud processing.