PEF to MOBI Converter

PEF to MOBI — create eBooks from images online for free

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File Security

Your uploaded PEF files are erased immediately after conversion, and the resulting MOBI is removed from servers within 24 hours — keeping your data private.

High Fidelity

Your PEF photos deserve clean output. The conversion engine produces MOBI files that maintain the visual character and detail of the source image.

Universal Access

The converter runs in any modern web browser. Use it on your desktop, laptop, tablet, or smartphone — no platform restrictions.

How to convert PEF to MOBI

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose mobi or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your mobi file right afterwards

About formats

PEF (Pentax Electronic Format) is the proprietary RAW image format used by Pentax digital SLR and mirrorless cameras, introduced in 2003 with the *ist D — Pentax's first digital SLR — and continuing through the current K-mount and medium-format 645 lineup. PEF files capture the unprocessed 12-bit or 14-bit readout from the camera's CMOS sensor in its native Bayer mosaic pattern, stored in a TIFF-based container with Huffman-coded lossless compression. The format includes embedded JPEG previews at multiple sizes, comprehensive EXIF metadata, and Pentax-specific MakerNote tags that record Custom Image mode settings, Shake Reduction (SR) gyroscope data, lens identification from the K-mount electronic interface, and the camera's Auto Level correction parameters. Pentax cameras are notable for their weather-sealed construction and compatibility with the vast legacy of K-mount lenses dating back to 1975, and PEF files from these bodies can include manual lens metadata entered through the camera's menu system. One advantage is the preservation of Pentax's distinctive color rendering — the brand's Custom Image modes (Bright, Natural, Reversal Film, Bleach Bypass, etc.) are stored as metadata rather than applied to the raw data, allowing photographers to explore different rendering interpretations during post-processing while the original sensor capture remains untouched. The format's longevity is another strength: PEF files from every Pentax DSLR are supported by Adobe Lightroom, Capture One, dcraw, RawTherapee, Pentax's own Digital Camera Utility, and other modern RAW processors.
Developer: Pentax
Initial release: 2003
MOBI is an ebook format originally developed by Mobipocket SA, a French company founded in 2000 that was later acquired by Amazon in 2005. The format builds on the PalmDOC/PDB container structure, adding support for HTML-based content markup, embedded images, a DRM layer, and a JavaScript subset for limited interactivity. MOBI files use a record-based database architecture inherited from Palm OS, with a header structure containing metadata like title, author, publisher, and language followed by compressed HTML content records. The format became the foundation of Amazon's early Kindle ecosystem — the original AZW format used on first-generation Kindles was essentially MOBI with Amazon's own DRM wrapper. MOBI supports reflowable text with basic formatting including bold, italic, headings, lists, and tables, as well as internal hyperlinks and a built-in table of contents. One advantage is broad device compatibility: MOBI files are recognized by Kindle devices and apps spanning over a decade of hardware, as well as numerous third-party readers on desktop and mobile platforms. The format's lightweight structure is another strength — even long novels produce compact files that load quickly on modest hardware. While Amazon has since moved to the more capable AZW3/KF8 format for new publishing, MOBI remains widely circulated in existing ebook libraries and continues to be produced by conversion tools like Calibre for maximum Kindle compatibility.
Developer: Mobipocket SA
Initial release: 2000

Frequently Asked Questions

Why convert PEF to MOBI?

Converting PEF to MOBI embeds your photo in an eBook-compatible format — making it possible to include Pentax images in digital reading materials.

What applications work with MOBI?

MOBI works with Kindle devices, Kindle app, Calibre, FBReader, and Mobipocket Reader.

How fast is the PEF to MOBI conversion?

Speed depends on file size, but most PEF to MOBI conversions complete in under a minute. Server-side processing ensures quick turnaround.

How long are converted files stored?

Converted MOBI files remain available for download for up to 24 hours, after which they are automatically deleted from Convertio servers.

Do I need to install software?

No — everything happens in your web browser. There is nothing to download or install for PEF to MOBI conversion on Convertio.