Add your XFDF file
Drop one or more .xfdf files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
XFDF to FDF
Converting a .xfdf font to .fdf repackages the same glyphs and metrics for a different delivery target. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop XFDF files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting XML Forms Data Format to Forms Data Format
Converting a .xfdf font to .fdf repackages the same glyphs and metrics for a different delivery target. An .xfdf file is the XML expression of PDF form data: a root <xfdf> element containing a <fields> tree in which each <field name="..."> holds a <value>. It carries the same information as FDF in a form that ordinary XML tooling can read.
An .fdf file holds the data from a PDF form without the form itself: field names and their values, stored in PDF's own object syntax, so the values can travel separately from the document and be merged back into it later. For this route the practical draw is far smaller than shipping a filled PDF for every response and defined inside the PDF specification rather than invented alongside it — balanced against binary-ish PDF syntax makes it awkward to inspect or generate by hand, which is worth knowing before you commit a large batch.
Why convert XFDF to FDF?
The practical trigger for this conversion is usually a mismatch: with .xfdf, considerably more verbose than FDF for the same data. Switching to .fdf buys you far smaller than shipping a filled PDF for every response, which is why it is the better fit for extracting submitted values from a PDF form workflow. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
XFDF vs FDF at a glance
| Aspect | XML Forms Data Format (.xfdf) | Forms Data Format (.fdf) |
|---|---|---|
| Format type | Text-based — characters and structure, so there is no visual quality loss | Text-based — characters and structure, so there is no visual quality loss |
| How it stores data | root element is <xfdf> in the http://ns.adobe.com/xfdf/ namespace, with fields under a single <fields> element | the file begins with %FDF-1.x and is otherwise a normal PDF object graph, so it needs a real PDF parser rather than a text scan |
| Strongest at | exchanging PDF form data with web services and enterprise systems | extracting submitted values from a PDF form workflow |
| Weak spot | considerably more verbose than FDF for the same data | binary-ish PDF syntax makes it awkward to inspect or generate by hand |
| Metadata | the href document reference is detected and reported as omitted rather than followed or copied | the referenced-document path is detected and deliberately omitted from the output rather than carried across |
Pick FDF as the output
Select .fdf in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if FDF is selectable, the route is real and validated.
Convert on your device
Press Convert. The font tables are parsed and rewritten locally with fonteditor-core; glyph outlines, hinting, and kerning survive the trip.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid FDF file. Outputs keep the original filename with the .fdf extension.
XFDF to FDF questions, answered
Will converting XFDF to FDF lose quality?
There is no visual quality to lose — xfdf is text-oriented and fdf is text-oriented, so the question is structural fidelity. Text, ordering, and basic structure are preserved; complex layout, embedded objects, and styling beyond the target's model are simplified.
Is it private to convert XFDF files here?
Yes — the .xfdf file is processed inside your browser tab and never uploaded. The font tables are parsed and rewritten locally with fonteditor-core; glyph outlines, hinting, and kerning survive the trip. Close the tab and the file is gone from memory.
Where will the FDF file work?
Adobe Acrobat, pdftk, iText and PDF form engines read FDF. Novus Convert parses it locally with a real PDF cursor and converts to XFDF and JSON. Files containing /URI, /Launch, /SubmitForm or /GoToR actions are refused rather than parsed, and any document reference is reported as omitted instead of being followed.
Will the FDF file be bigger or smaller than my XFDF?
It depends on the content: the file begins with %FDF-1.x and is otherwise a normal PDF object graph, so it needs a real PDF parser rather than a text scan. Convert one representative file first and compare before batch-processing a large set.
What happens to the metadata in my XFDF file?
In .xfdf, the href document reference is detected and reported as omitted rather than followed or copied. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.
Can I convert FDF back to XFDF?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .xfdf → .fdf → .xfdf is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.