K25 to FB2 Converter
FileFlip converts K25 to FB2 entirely inside your browser, using ImageMagick, MuPDF and Pandoc compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert a K25 file to FB2?#
- Drop your K25 file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to FB2 and the conversion starts on its own. FileFlip downloads 79.9 MB of WebAssembly the first time and nothing after that, then runs ImageMagick, MuPDF and Pandoc on your own machine.
- Save the FB2 file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting K25 to FB2 lose quality?#
No. The K25 picture is placed into the FB2 document at its full resolution, so every pixel reaches it intact. What you give up is that it becomes a picture inside a document rather than text.
Is it safe to convert K25 files online?#
Yes, because nothing is uploaded. FileFlip converts K25 files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What K25 to FB2 actually does to the file#
Converting K25 to FB2 runs on ImageMagick, MuPDF and Pandoc, downloads 79.9 MB of WebAssembly the first time and nothing after that, places the picture into the document at full resolution.
| Engine | ImageMagick, MuPDF and Pandoc |
|---|---|
| Conversion path | 3 steps: K25 → PNG → HTML → FB2 |
| Downloaded to your browser | 79.9 MB, once, then cached by your browser |
| Quality | Pixels preserved |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
Worth knowing before you start:
- camera raw is demosaiced with ImageMagick's defaults, which will not match the camera's own rendering
- the picture is placed in the document as a picture; no text is recognised out of it
- the file passes through HTML on the way, so anything HTML cannot express does not survive
- some cameras write lossily compressed raw, so the source is not always a complete sensor record
What is a K25 file?#
A K25 file holds the raw sensor dump written only by the Kodak DC25, a 1996 consumer digital camera and one of the first to save photos to a removable CompactFlash card.
K25 only comes up when opening images pulled from an original Kodak DC25 memory card; there is no reason to create one today.
Convert K25 to TIFF or PNG for long-term storage, since almost no current photo software recognizes the format directly.
What is an FB2 file?#
An FB2 file is a single XML document that holds an entire book's text, metadata and base64-encoded cover images, in the FictionBook format that originated in the Russian-language ebook scene.
Keep a book as FB2 when it is sourced from a Russian-language ebook library and the reader is FB2-native, such as FBReader or a PocketBook device.
Convert FB2 to EPUB to read the book on a device or app outside the small set of readers that understand FictionBook directly.
K25 to FB2 questions people ask#
What camera made this K25 file?
A K25 file comes exclusively from the Kodak DC25, a consumer digital camera released in 1996. No other camera ever wrote this format.
What still opens a K25 file today?
K25 files open in raw converters built on the LibRaw library, such as RawTherapee and darktable, which still list the Kodak DC25 among their supported cameras. Kodak's own software for the camera is long unsupported.
Is K25 the same as other Kodak raw formats like DCR or KDC?
No. K25 is specific to the Kodak DC25, while DCR belongs to Kodak's professional DCS-series cameras and KDC belongs to later Kodak consumer models. The extensions come from the same manufacturer but are not interchangeable.
What is an FB2 file?
An FB2 file is an ebook in the FictionBook format, a single XML document that holds the full text, metadata and any cover image in one file rather than the zipped archive EPUB uses. It was created in 2004 and is most common in Russian-language ebook collections.