What happens when you convert PDF to PDB
- The PDF is converted by Calibre, the widely used open-source e-book manager, on our conversion server.
- A PDF has fixed pages rather than flowing text, so Calibre rebuilds the text flow from the page layout, then writes it as a PalmDoc e-book. Scanned PDFs are images of pages with no text, so they give an empty book.
- PalmDoc holds plain text only, so images, fonts and formatting are left out.
- This conversion runs on our 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. Files up to 25 MB are accepted.
How to convert PDF to PDB online
- Press "Choose PDF files" and select one or more files, or drag them onto the box. Files up to 25 MB each can be converted.
- There are no settings to choose: the converter keeps everything the target format can hold.
- Press "Convert to PDB". The file is uploaded to our conversion server, converted in a few seconds, and deleted together with the result as soon as the result is sent back.
- Save each PDB with its download button. Our server has already deleted both your PDF and the PDB by then.
Why convert PDF to PDB?
PDF files usually come from documents, forms, invoices and print-ready files. People convert them to PDB because PDB is what Palm handhelds and some old e-reader apps read.
In short, PDF is good at what it was made for, and PDB is the more practical choice when the file has to open, upload or print somewhere else. PDF opens in every browser's built-in viewer, while PDB opens in Calibre; current phones and e-readers need an app.
How to convert PDF to PDB on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your PDF files in from File Explorer, and press Convert. Each PDB is saved to your Downloads folder.
On a Mac
Safari, Chrome and Firefox all work. Drag the PDF files from Finder onto the drop zone and the PDB files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose PDF files. You can pick from Photos or from the Files app. The converted PDB appears in Files, in the Downloads folder.
On Android
Open the page in Chrome, tap Choose PDF files and pick them from Files or your gallery. The PDB is saved to the Download folder, where any file manager can find it.
Best settings for PDF to PDB
There are no settings: the text is written as PalmDoc, the kind of PDB that most Palm reading apps and Calibre open.
Keep the original file; each conversion rebuilds the book, and converting back will not restore what the target could not hold.
PDF vs PDB: the differences
| PDB | ||
|---|---|---|
| Full name | Portable Document Format | Palm database e-book |
| Type | document | e-book |
| Created by | Adobe | Palm |
| First released | 1993 | 1996 |
| Compression | Lossy or lossless | Lossless |
| Transparency | No | n/a |
| Animation | No | n/a |
| Vector or raster | Vector | n/a |
| Colour | any colour, pages can mix text, vectors and images | n/a |
| What it holds | any colour, pages can mix text, vectors and images | the text of a book in one of several Palm reader formats, such as PalmDoc or eReader |
| In a browser | opens in every browser's built-in viewer | opens in Calibre; current phones and e-readers need an app |
| Common uses | documents, forms, invoices and print-ready files | e-books for Palm handhelds and old eReader purchases |
| MIME type | application/pdf | application/vnd.palm |
About PDF and PDB files
What is a PDF file?
A PDF fixes the layout of every page so it looks the same on any device. Converting a PDF to an image renders each page to pixels; converting an image to PDF wraps it as a page.
What is a PDB file?
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.
PDF to PDB not working? Common problems
- "Files up to 25 MB can be converted." Server conversions have a size limit. Compress the images inside the file, or split it, and try again.
- "The conversion took too long and was stopped." Very long or complex files can pass the 90 second limit. Split the file and convert the parts.
- "This file is not really in PDF format." The converter checks every file before it runs anything, so a file of another format renamed to .pdf is refused. Choose the page for its real format.
Convert PDF to PDB from the command line
This page uses Calibre. Installed on your computer, its ebook-convert command does the same conversion:
ebook-convert input.pdf output.pdbConverting 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.
PDF to PDB converter FAQ
Will I lose quality converting PDF to PDB?
The words are kept, but a PDF's fixed layout has to be turned into flowing text, so complex pages can come out jumbled. Images and formatting are left out.
Why is the PDB a different size from the PDF?
Much smaller than the PDF, because only the text is kept.
Are my PDF files uploaded?
Yes, for this conversion. A faithful PDF to PDB conversion needs Calibre, the open-source e-book manager, which cannot run in a browser. The file travels over an encrypted connection, is converted in a private temporary folder, and is deleted together with the PDB as soon as the result has been sent back to you. We do not keep, read or share it.
Can I convert several PDF files to PDB at once?
Yes. Select or drop as many files as you like; they are converted one after another and each gets its own download button.
How do I open a PDB file?
PDB opens in Calibre; current phones and e-readers need an app. PDB is common for e-books for Palm handhelds and old eReader purchases.
Is this PDF to PDB converter free?
Yes. There is no sign-up and no watermark. Because this conversion uses our server, there is a fair-use limit of 25 MB per file and a number of files per hour, which stops the service being overloaded.
Can I convert PDF to PDB on my phone?
Yes. It works in Safari on iPhone and iPad and in Chrome on Android. The conversion happens on our server, so it is as fast on a phone as on a computer; the PDB is saved to your Downloads folder.