DOC to MOBI Converter
Convert DOC to MOBI online for free. Fast, secure, and high-quality conversion with no sign-up or software required.
Maximum file size is 1GB
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Three steps to your converted file
Everything happens in your browser tab - upload, pick a format, download. The heavy lifting runs on our servers.
Upload your file
Drag and drop, click to browse, or paste a URL. Batches take up to 20 files at once - 230+ input formats across video, audio, image, document, and archive types.
Choose an output format
Pick from over a hundred output formats. Filter by category or search by name - every option is open to everyone, no account needed.
Convert & download
Hit Convert and grab your download link moments later. Originals are erased when the job completes; results are cleared within about an hour.
What is a DOC file?
The DOC extension refers to the proprietary binary file format used by Microsoft Word versions 97 through 2003. It is structured around the Object Linking and Embedding (OLE) Compound File Binary (CFB) format, acting as a file system within a file that manages streams and storages for text, formatting, scripts, and metadata. Unlike modern XML-based alternatives, DOC files store data in binary records, which can make parsing complex and prone to corruption if the binary headers are damaged.
How to open a DOC file
Microsoft Word remains the primary software for full-feature support of the DOC binary format. However, owing to its ubiquity, most third-party word processors including LibreOffice Writer, Apache OpenOffice, and Corel WordPerfect provide reverse-engineered support for opening and editing these files. Google Docs also offers import capabilities, though complex formatting utilizing legacy OLE objects may experience rendering shifts during conversion.
DOC Technical Info
- Full Name
- Microsoft Word Binary File
- Developed By
- Microsoft
- Initial Release
- 1983
- MIME Type
- application/msword
What is a MOBI file?
The Mobipocket eBook format (MOBI) is a binary distribution format developed by Mobipocket SA in 2000, utilizing the Open eBook (OEB) standard and XHTML for reflowable content layout. Encapsulated within a Palm Database (PDB) container, MOBI files employ either the LZ77-based PalmDOC compression or the proprietary HUFF/CDIC algorithm to minimize file size. The format supports Digital Rights Management (DRM), metadata indexing, and javascript capabilities, serving as the foundational architecture for Amazon's proprietary AZW format before the adoption of KF8.
How to open a MOBI file
Native support for MOBI is restricted primarily to Amazon Kindle hardware and legacy Mobipocket readers. On Windows, macOS, and Linux, users require third-party eBook management software such as Calibre, which offers comprehensive viewing and conversion capabilities. Alternatively, the Kindle Previewer tool provided by Amazon or multi-format readers like FBReader and Sumatra PDF can render the unencrypted content of these archives.
MOBI Technical Info
- Full Name
- Mobipocket eBook Format
- Developed By
- Mobipocket SA
- Initial Release
- 2000
- MIME Type
- application/x-mobipocket-ebook
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The fastest way to convert any file
Purpose-built for speed, privacy, and breadth of format support.
Convert DOC to MOBI in seconds
Every DOC to MOBI conversion runs on our servers, so your device stays fast and the output quality stays intact.
Fast, cloud-powered
No queue, no waiting. Files are processed on high-performance servers and returned in seconds, even for large files.
Secure & private
Encrypted in transit and never shared with anyone. Uploads are erased the moment your job completes, and results shortly after.
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Developer API
Convert DOC to MOBI via API
Automate DOC to MOBI conversions in three steps: create a job, upload your file, then poll for the result.
# 1. Create job
curl -X POST https://api.runconvert.com/v3/jobs \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"tag": "doc-to-mobi",
"tasks": {
"upload-file": {
"operation": "import/upload"
},
"convert": {
"operation": "convert",
"input": "upload-file",
"output_format": "mobi"
},
"export-result": {
"operation": "export/url",
"input": "convert"
}
}
}'
# 2. Upload your file (use upload_url from the response)
curl -X PUT "$UPLOAD_URL" --upload-file input.doc
# 3. Poll for result
curl https://api.runconvert.com/v3/jobs/$JOB_ID?include=tasks \
-H "Authorization: Bearer YOUR_API_KEY"Replace YOUR_API_KEY with your RunConvert API key. Get your free API key at runconvert.com/api.