EPUB vs PDB — Comparison & Free Converter
Fast, instant EPUB to PDB conversion. No signup required. Just drop your .epub file and get .pdb in seconds.
Batch Settings
お気に入りの電子書籍を、より多くのデバイスで快適に読みたいとお考えですか？EPUB形式は広く普及していますが、Palm OSを搭載した旧型PDAや一部の電子辞書などでは、PDB形式が今もなお現役で活躍しています。特に、長年大切にされているデバイスで、お持ちの漫画やビジネス文書を読みたい場合、EPUBからPDBへの変換は非常に有効な手段となります。当社の変換ツールは、文字化けやレイアウト崩れのリスクを最小限に抑えつつ、スムーズな変換を実現します。縦書きの表現や、特定のフォント設定が重要なコンテンツでも、可能な限り元の意図を保ったPDBファイルを作成できるよう、細心の注意を払っております。古き良きデバイスで、新しい読書体験を始めてみませんか。
- 旧型電子辞書での小説閲覧
- ビジネス文書のモバイル確認
- 自炊漫画のPDB化
PDB形式はPalm OSが主流だった時代に日本でも広く利用され、特に電子辞書や一部のPDAでは今もなお根強い需要があります。EPUBからの変換では、縦書きやルビの再現性が課題となることがありますが、当ツールでは可能な限り対応します。
About EPUB to PDB Conversion
EPUB or PDB — which format should you use? The answer depends on your needs. Here's a quick breakdown.
EPUB is the standard e-book format supported by most readers except Kindle. It has mostly universal platform support. PDB is a widely used file format. It has common platform support.
So when should you convert EPUB to PDB? This conversion is ideal when you When you need a PDB file. This conversion helps you convert between formats quickly.
Converting EPUB to PDB maintains high quality with CocoConvert's optimised encoder settings.
If you've decided PDB is the right choice, CocoConvert makes the conversion effortless. Upload your .epub file, pick PDB, and click Convert — done in seconds. The converter runs on secure servers in Germany, powered by FFmpeg, Sharp, and qpdf. Files are encrypted via TLS and erased within 24 hours.
Free tier: 5 files/hour, 250 MB each. Pro: 100 files/hour, 5 GB each. Works in every modern browser on desktop and mobile.
How to Convert EPUB to PDB
- 1
Choose your EPUB file
Upload your .epub file using drag-and-drop or the file browser. Batch mode lets you add multiple files.
- 2
Set format to PDB
Select .pdb from the output options. The converter applies optimal quality settings automatically.
- 3
Run the conversion
Click Convert. Server-side processing means your device stays fast — even for large ebook files.
- 4
Get your PDB file
Download your converted file instantly. Batch downloads are available as a zip archive.
What Happens When You Convert EPUB to PDB
Your EPUB file is decoded and re-encoded as PDB.
Your EPUB file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in PDB format
The converted file is ready for download
Format Comparison
EPUB
.epub file
| Extension | .epub |
| MIME Type | application/epub+zip |
| Category | eBook |
PDB
.pdb file
| Extension | .pdb |
| MIME Type | application/vnd.palm |
| Category | eBook |
Should You Convert EPUB to PDB?
When to Convert
- ✓When you need a PDB file
Frequently Asked Questions
Should I use EPUB or PDB?
It depends on your goal. EPUB preserves full quality. PDB preserves full quality. Choose based on whether file size or quality matters more for your use case.
Is PDB higher quality than EPUB?
Not necessarily. Converting EPUB to PDB maintains high quality with CocoConvert's optimised encoder settings. Quality depends on the compression type and settings, not just the format name.
Can I convert EPUB to PDB on Mac and Windows?
Yes. CocoConvert is a web-based tool that works in all modern browsers — Chrome, Safari, Firefox, Edge — on any operating system including macOS, Windows, Linux, iOS, and Android.
Is CocoConvert free for EPUB to PDB?
Yes. Free users get 5 conversions per hour (250 MB each). Pro subscribers unlock 100 files per hour, 5 GB per file, and priority processing.
What tools does CocoConvert use for EPUB to PDB?
CocoConvert uses FFmpeg for audio/video, Sharp for images, and qpdf for documents — the same open-source libraries used by Netflix, YouTube, and major enterprise platforms.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.