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Cortex supports a comprehensive range of file formats for document processing. Files are automatically parsed and their content extracted for indexing and search. This page provides a complete reference of all supported formats.
Unsupported File Formats: If you attempt to upload a file format that is not supported, you will receive an error response with status code 400 and the message: "Unsupported file format: [filename]. Please check our supported file formats documentation." Ensure your files are in one of the supported formats listed below before uploading.

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Word Processing and Presentations

Office documents and presentation files:
  • PDF
  • ODT (OpenDocument Text)
  • RTF (Rich Text Format)
  • DOC
  • DOCX (Office Open XML)
  • DOCM, DOT, DOTM
  • Pages
  • CWK, LWP, MW, MCW, HWP, PBD, zabw
  • WPD, WPS
  • XML
  • Key
  • PPT, PPTX, PPTM, POT, POTM, POTX, SDD, SDA, SDP, SGL, STI, SXI, STW, SXW, SXG, UOP

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Spreadsheets

Data and spreadsheet formats:
  • XLSX
  • XLS
  • XLSM, XLSB, XLW, CSV, TSV, DIF, SYLK, SLK, PRN, NUMBERS, ET, ODS, FODS, UOS1, UOS2, DBF, WK1, WK2, WK3, WK4, WKS, 123, WQ1, WQ2, WB1, WB2, WB3, QPW, XLR, ETH

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Markup and Documentation

These formats are ideal for documentation, wikis, and structured text content:
  • Markdown (all variants: CommonMark, GitHub-Flavored, MultiMarkdown, Markdown Extra, Djot)
  • HTML, XHTML
  • LaTeX
  • reStructuredText
  • Textile
  • Emacs Org-Mode
  • Emacs Muse
  • OPML
  • DocBook
  • AsciiDoc
  • MediaWiki, TWiki, DokuWiki, TikiWiki, Vimwiki, Muse Wiki
  • JATS, BITS
  • FictionBook2 (FB2)
  • GNU TexInfo
  • Haddock markup
  • TEI Simple
  • Typst
  • pod, man (roff), mdoc
  • Creole, Jira wiki markup
  • Markua, txt2tags
  • Plain text (TXT)

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Images

Image files with text content:
  • JPEG, JPG, PNG, GIF, BMP, SVG, TIFF, WEBP
Image Processing: Image files are processed using OCR (Optical Character Recognition) to extract text content. Ensure images have clear, readable text for best results.

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Ebooks

Digital book formats:
  • EPUB
  • FictionBook2 (FB2)

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Data/Bibliography/Serialization

Structured data and reference formats:
  • BibTeX/BibLaTeX/CSL JSON/CSL YAML
  • RIS
  • EndNote XML
  • Jupyter notebook (ipynb)
  • JSON
  • XML
  • Haskell AST

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Others (Special Formats)

Specialized and niche formats:
  • InDesign ICML
  • XWiki, ZimWiki
  • Beamer, Slidy, Slideous, S5, DZSlides, reveal.js (presentation/slideshow formats)
  • ANSI-formatted text

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File Size and Processing Limits

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File Size Limits

  • Maximum file size: 50MB per file
  • Recommended size: Under 10MB for optimal processing speed
  • Large files: Files over 100 pages may take longer to process

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Processing Time

Cortex is optimized for speed and typically processes files much faster than traditional solutions:
  • Small files (< 10 pages): Under 2 minutes (typically 30 seconds to 1 minute)
  • Medium files (10-100 pages): 2-5 minutes (typically 1-3 minutes)
  • Large files (100+ pages): 5-15 minutes (typically 3-8 minutes)
Performance Note: Cortex’s processing times are significantly faster than traditional document processing solutions. Most files under 10 pages are processed in under 2 minutes, with many completing in under 1 minute.

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Best Practices

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File Preparation

  • Ensure files are not password-protected
  • Use clear, well-structured documents for better parsing
  • Avoid corrupted or damaged files
  • Use descriptive filenames for easier identification

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Format-Specific Tips

PDF Files:
  • Use text-based PDFs rather than scanned images when possible
  • Ensure proper text encoding (UTF-8 preferred)
  • Avoid password-protected or encrypted PDFs
Office Documents:
  • Save in the latest format version when possible
  • Remove unnecessary formatting that might interfere with parsing
  • Ensure all content is accessible (not hidden or in comments only)
Images:
  • Use high-resolution images with clear, readable text
  • Ensure good contrast between text and background
  • Avoid heavily stylized fonts that might be difficult to OCR
Markdown:
  • Use standard Markdown syntax for best compatibility
  • Include proper heading structure for better chunking
  • Use consistent formatting throughout the document

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Troubleshooting

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Common Issues

File Not Processing:
  • Check if the file format is supported (see list above)
  • Verify the file is not corrupted or password-protected
  • Ensure the file size is under 50MB
  • Check your API key permissions
Poor Text Extraction:
  • For images: ensure high resolution and clear text
  • For PDFs: use text-based rather than scanned PDFs
  • For office docs: avoid complex formatting or embedded objects
Processing Errors:
  • Check the file format against the supported list
  • Verify file integrity (not corrupted)
  • Ensure proper file permissions
  • Contact support with the file_id if issues persist
Need Help? If you’re experiencing issues with file processing or have questions about format support, contact our support team at founders@usecortex.ai with the file_id for assistance.