What is a PDB file?
PDB stands for Palm database e-book. It was created by Palm and first released in 1996. PDB is the Palm OS database format, which several e-book readers on Palm handhelds used: PalmDoc, eReader, Plucker and others. The extension alone does not say which, so a PDB may open in one app and not another. Calibre reads the common kinds.
| Type | e-book |
|---|---|
| Compression | Lossless |
| In a browser | opens in Calibre; current phones and e-readers need an app |
| Common uses | e-books for Palm handhelds and old eReader purchases |
| MIME type | application/vnd.palm |
How to open a PDB file
Whether a PDB file opens with a double click depends on the device. Here is what works on each, without buying software:
| Windows | Calibre, a free e-book manager, opens every e-book format; the Kindle app opens MOBI and AZW3. |
|---|---|
| Mac | Apple Books opens EPUB; Calibre and the Kindle app open MOBI and AZW3. |
| iPhone and iPad | Apple Books opens EPUB; the Kindle app opens books sent to your Amazon account. |
| Android | Google Play Books opens EPUB; FBReader opens EPUB and FB2; the Kindle app opens Amazon books. |
| Web browser | PDB opens in Calibre; current phones and e-readers need an app. |
Want the technical details? See what a .pdb file is, with its MIME type, file signature and a viewer.
PDB compared with other e-book formats
How PDB stacks up against the formats people most often convert it to or from:
| Format | Compression | Usually contains | Released | Best for |
|---|---|---|---|---|
| PDB | Lossless | the text of a book in one of several Palm reader formats, such as PalmDoc or eReader | 1996 | e-books for Palm handhelds and old eReader purchases |
| EPUB | Lossless | chapters as XHTML pages, with images and a table of contents | 2007 | e-books from stores other than Amazon and free e-book libraries |
| AZW3 | Lossless | a book's text, images, styling and table of contents | 2011 | Kindle e-readers and books loaded onto them over USB |
| MOBI | Lossless | a book's text, images and table of contents | 2000 | older Kindle e-readers and e-books from the 2000s |
| FB2 | Lossless | a book's text, structure and metadata as a single XML file | 2004 | e-books from Russian and Eastern European libraries |
How to use the PDB converter
- Choose the format you want in the Convert to menu.
- Drop your PDB files on the box, or press Choose PDB files. Several files can go in at once.
- Adjust the settings if you need to; the defaults suit most people.
- Press Convert and save each file with its Download button. The file is converted on our server and deleted as soon as the result is sent back.
Tips for converting PDB files
Converting a PDB file keeps the book's text, chapters and images; what changes is how it is packaged for each reader. A few habits give the best result.
- For a current Kindle, send EPUB through Send to Kindle, or copy AZW3 over USB. MOBI is for older Kindles.
- Books with DRM cannot be converted. DRM-free books from Project Gutenberg, Standard Ebooks and independent authors convert normally.
- Keep the original file; each conversion rebuilds the book.
- For PDF to EPUB, a PDF made from a text document converts far better than a scan or a multi-column layout.
- Calibre, the engine used here, is free for your own computer too, and handles whole libraries at once.
Convert PDB files from the command line
This page uses Calibre. Installed on your computer, its ebook-convert command does the same conversion:
ebook-convert input.pdb output.epubConverting on your own computer keeps the file entirely local, which is worth it for very large or very sensitive documents. For everything else, the converter on this page does it without installing anything.
PDB converter FAQ
What is a PDB file?
PDB stands for Palm database e-book, an e-book format created by Palm in 1996. PDB is the Palm OS database format, which several e-book readers on Palm handhelds used: PalmDoc, eReader, Plucker and others. The extension alone does not say which, so a PDB may open in one app and not another. Calibre reads the common kinds.
How do I open a PDB file?
PDB opens in Calibre; current phones and e-readers need an app. If the program you need will not open it, convert it to a more widely supported format above.
What is the most common PDB conversion?
PDB to EPUB is the conversion people search for most. The PDB is converted by Calibre, the widely used open-source e-book manager, on our conversion server.
Does converting PDB files here upload them?
Yes. PDB conversions need Calibre, an open-source program that cannot run in a browser, so they run on our conversion server. The file is uploaded, converted, and deleted together with the result as soon as the result has been sent back to you. Nothing is kept.
Is the PDB converter free?
Yes. There is no sign-up and no watermark. Conversions that use our server accept files up to 25 MB, with a fair-use limit per hour. The site is supported by advertising.
Can I convert PDB files on iPhone or Android?
Yes. Open this page in Safari on iPhone and iPad, or in Chrome on Android, choose your PDB files and download the results to your Downloads folder.
Can I convert several PDB files at once?
Yes. Drop as many as you like; they are converted one after another, each with its own download button.