LRF vs PDB
A detailed comparison of Sony LRF eBook and PalmDOC eBook — file size, quality, compatibility, and which format to choose for your workflow.
Sony LRF eBook
eBooksLRF (BBeB Book) is a proprietary ebook format developed by Sony for their Reader line of e-ink devices. It supports reflowable text, images, and basic formatting, but has been superseded by EPUB on newer Sony Reader models.
About LRF filesPalmDOC eBook
eBooksPDB (Palm Database) is a generic database format from the Palm OS era that was widely used for ebooks on Palm handheld devices. PalmDOC and Mobipocket both use PDB as their underlying container for storing text-based ebook content.
About PDB filesStrengths Comparison
LRF Strengths
- Sony PRS-native.
- Rich layout.
- Calibre-readable.
PDB Strengths
- Compact record-based structure for low-RAM devices.
- Basis of PalmDOC, Mobipocket, eReader, and Kindle AZW formats.
- Well-documented.
- Simple to parse — stable for 30 years.
Limitations
LRF Limitations
- Deprecated.
- Sony exited the market.
- No new content.
PDB Limitations
- Ecosystem collapsed with Palm's hardware business.
- Name collides with biochemistry's Protein Data Bank PDB.
- Modern ebook tooling prefers EPUB, AZW3, or direct formats.
- Very little new content written as PDB in 2026.
Technical Specifications
| Specification | LRF | PDB |
|---|---|---|
| MIME type | application/x-sony-bbeb | — |
| Extension | .lrf | .pdb |
| Native reader | Sony PRS series (retired 2014) | — |
| MIME types | — | application/vnd.palm (Palm), chemical/x-pdb (biochemistry) |
| Palm structure | — | Header + record list + record data |
| Related formats | — | PalmDOC, Mobipocket MOBI, AZW |
| Namespace clash | — | Biochemistry Protein Data Bank is a different format entirely |
Typical File Sizes
LRF
- Typical novel 500 KB - 3 MB
PDB
- PalmDOC ebook (text novel) 200 KB - 2 MB
- PalmOS app data store 10 KB - 500 KB
- Protein Data Bank file (biochemistry) 50 KB - 5 MB
Ready to convert?
Convert between LRF and PDB online, free, and without installing anything. Encrypted upload, automatic deletion after 60 minutes.
Frequently Asked Questions
LRF (Sony LRF eBook) is an ebook format designed for reading long-form text on dedicated e-readers, tablets, and ebook apps. It is part of the ebooks family and typically supports reflowable text, embedded images, chapter navigation, cover art, and metadata (title, author, ISBN) in a portable package.
LRF (Sony LRF eBook) is an ebook formato designed para reading long-form text on dedicated e-readers, tablets, e ebook apps. It is part of the ebooks family e tipicamente suporta reflowable text, embedded images, chapter navigation, cover art, e metadata (title, author, ISBN) em um portable package.
Dedicated e-readers — Kindle, Kobo, Nook, Pocketbook — support the most common ebook formats. On phones, Apple Books, Google Play Books, Moon+ Reader and KOReader all handle LRF. For desktop reading, Calibre is the universal ebook viewer and library manager. Convert to EPUB or PDF for maximum compatibility.
Dedicated e-readers — Kindle, Kobo, Nook, Pocketbook — support the most common ebook formatoos. On phones, Apple Books, Google reproduzir Books, Moon+ Reader e KOReader all handle LRF. para desktop reading, Calibre is the universal ebook viewer e library manager. converter to EPUB ou PDF para máximo compatibilidade.
Upload your LRF to KaijuConverter and pick EPUB, MOBI, PDF, AZW3, or similar targets. Our Calibre-powered pipeline preserves chapter structure, embedded images, cover art, and metadata. Conversion takes seconds for typical novels; long technical books with many images may take a little longer.
EPUB is the open ebook standard — it plays on every e-reader except older Kindles and in every major ebook app. PDF is better for fixed-layout content (textbooks, coffee-table books) and printing. Pick EPUB when the ebook is reflowable text, PDF when the layout matters more than the reading experience.