> ## Documentation Index
> Fetch the complete documentation index at: https://docs.libratech.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# File types & previews

> Which formats Libra accepts, how each one previews in the document viewer, and which formats support translation and anonymisation.

<video autoPlay muted loop playsInline src="https://mintcdn.com/libra-4206ec93/azhR9hqtFjs66ITC/assets/videos/features/documents-file-types.webm?fit=max&auto=format&n=azhR9hqtFjs66ITC&q=85&s=5028c57464d5c92cbb240cf15c59ef9e" className="rounded-xl border w-full" data-path="assets/videos/features/documents-file-types.webm" />

Libra takes far more than PDFs. Office documents, images, emails, spreadsheets, plain text and audio recordings all upload into **Project files**, and the text in each one is extracted so it can be searched, answered from, and cited.

What differs between formats is the *preview*. Some files open in the full PDF viewer, some render as an inline image or a plain-text pane, and a few upload and index perfectly well without ever opening in the viewer.

<div className="libra-buddy-callout">
  <img src="https://mintcdn.com/libra-4206ec93/wgVZXcGnHS4aJk9T/assets/images/libra-buddy/excited.png?fit=max&auto=format&n=wgVZXcGnHS4aJk9T&q=85&s=ff4421471ed769b8a6bb79c03cda38f3" alt="Libra mascot excited" width="729" height="648" data-path="assets/images/libra-buddy/excited.png" />

  <div className="libra-buddy-callout-content">
    Word files convert to PDF for preview, but the original is preserved; **Download** always returns what you uploaded, never the converted PDF. Handy for handing back source.
  </div>
</div>

## What Libra accepts

| Family         | Extensions                                                         | How it previews                                                                            |
| -------------- | ------------------------------------------------------------------ | ------------------------------------------------------------------------------------------ |
| **PDF**        | `.pdf`                                                             | The full viewer: page navigation, zoom, and citation jumps that land on the cited passage. |
| **Word**       | `.docx`, `.doc`, `.rtf`, `.odt`                                    | Converted to PDF on upload, then behaves exactly like a PDF.                               |
| **PowerPoint** | `.pptx`, `.ppt`, `.ppsx`, `.pps`, `.odp`                           | Converted to PDF on upload, then behaves exactly like a PDF.                               |
| **Excel**      | `.xlsx`, `.xls`                                                    | Rendered server-side as an HTML table per sheet. `.ods` converts to PDF instead.           |
| **Images**     | `.png`, `.jpg`, `.jpeg`, `.gif`, `.webp`                           | Shown inline, scaled to fit the pane.                                                      |
| **Email**      | `.eml`                                                             | Parsed into a header block plus the message body.                                          |
| **Text**       | `.txt`, `.md`, `.log`, `.csv`, `.xml`, `.json`                     | Plain-text pane, monospaced.                                                               |
| **HTML**       | `.html`, `.htm`                                                    | Sanitised and rendered in a sandboxed frame.                                               |
| **Audio**      | `.mp3`, `.m4a`, `.wav`, `.flac`, `.ogg`, `.mpeg`, `.mpga`, `.webm` | Transcribed on upload. No preview — the transcript is what gets indexed.                   |

A further set of formats uploads and indexes but has no preview of its own: `.msg` Outlook messages, `.tiff` / `.tif` scans, and a long list of plain-text and source-code extensions (`.rst`, `.ini`, `.conf`, `.sql`, `.py`, `.js` and similar). Their text is searchable and citable; they just don't open in the viewer.

<Note>
  `.svg` and `.bmp` are **not** accepted. Drop either into an upload and it is skipped as an unsupported file type. Convert to PNG first.
</Note>

Files are capped at 500 MB each and 1,000 per chat. Very large spreadsheets are the one case where a file well inside the size cap can still be refused during processing; the [FAQ](/en/resources/faq) has those bounds.

## Format-specific notes

<AccordionGroup>
  <Accordion title="PDFs">
    The richest preview. Page navigation, zoom and citation jumps — arrive from an answer and the cited passage is highlighted for you — plus the **Translate** and **Anonymize** actions in the toolbar where your subscription includes them.
  </Accordion>

  <Accordion title="Word documents">
    Word files are converted to PDF on upload, so the preview behaves identically to a PDF — including page controls, zoom and anonymisation. The original is preserved; **Download** returns the editable file you uploaded.

    To edit a Word document in place with AI assistance, use the [Word Add-in](/en/integrations/word/setup).
  </Accordion>

  <Accordion title="PowerPoint and OpenDocument">
    `.pptx`, `.ppt`, `.ppsx`, `.pps` and `.odp` decks convert to PDF, as do `.odt` documents and `.ods` spreadsheets. Once converted they behave like any other PDF in the viewer, and the original stays available for download.
  </Accordion>

  <Accordion title="Excel">
    `.xlsx` and `.xls` workbooks are parsed on the server and rendered as one scrolling HTML document, with each sheet under its own heading. It is a read-only rendering in a sandboxed frame — there are no sheet tabs and the cells are not clickable. Long sheets are truncated for the preview; the full workbook is still indexed.

    `.csv` is not treated as a spreadsheet. It opens in the plain-text pane, though the **File type** filter in Project files still groups it under **Excel**.
  </Accordion>

  <Accordion title="Images">
    Rendered inline and scaled to fit the pane. There are no zoom or pan controls — zoom is a PDF-viewer feature.

    Text in images is extracted automatically, so a photographed or scanned page is searchable and citable once processing finishes. `.tiff` scans are text-extracted the same way but have no inline preview.
  </Accordion>

  <Accordion title="Emails (.eml)">
    The viewer shows the Subject, then From, To, Cc and Date, then the message body. Where the email carries an HTML part, that part is rendered — sanitised, with inline images embedded and any external references stripped. Plain-text-only emails render as text.

    Attachments are not listed in this preview. Upload the attachments you need as their own files.

    `.msg` files upload and index but do not open in this preview. Emails exported into a project from the [Outlook Add-in](/en/integrations/outlook/setup) arrive with a PDF conversion, so they open in the PDF viewer.
  </Accordion>

  <Accordion title="Text and structured text">
    `.txt`, `.md`, `.log`, `.csv`, `.xml` and `.json` render as monospaced plain text, with no syntax colouring and no formatting. Useful for transcripts, exports and logs.

    For anything you want to analyse rather than read, point a Discovery at the file instead of opening it here.
  </Accordion>

  <Accordion title="HTML">
    `.html` and `.htm` files are sanitised on the server — scripts and styles stripped, external resource loads blocked — and rendered in a sandboxed frame. Useful for archived web pages and saved articles.
  </Accordion>

  <Accordion title="Audio">
    Audio uploads are transcribed, and the transcript is what Libra searches and cites. There is no player in the document viewer.
  </Accordion>
</AccordionGroup>

<Note>
  Email, Excel and HTML previews are generated on the server at the moment you open them, and that generation is capped at 10 MB. A larger `.eml`, `.xlsx` or `.html` file uploads and indexes normally, but the preview itself fails to load. Search, answers and citations still work on it.
</Note>

## Working in the viewer

The tab strip and the **Download** button are there whatever the file is. The page, zoom, **Translate** and **Anonymize** controls appear only on the PDF path.

**Tabs.** Every document you open becomes a tab along the top. Click a tab to switch, drag a tab to reorder, and click the **×** on a tab to close it. Once more than one tab is open, arrows appear for stepping through them. Opening an answer's sources adds a single **Citation list** tab at the front of the row — it is re-pointed at whichever answer you came from rather than stacking up one tab per answer.

**Download.** The toolbar has a **Download** button on every preview, and it returns the original file. A Word document downloads as `.docx`, not as the converted PDF.

**Translate.** PDFs and `.docx` files can be translated into another language from the toolbar, up to 30 MB per file and subject to a daily limit. Translations open as their own document.

**Anonymize.** Where your subscription includes it, PDFs — and therefore anything converted to PDF — can have personal data removed in one click from the toolbar. It is marked **Beta**, capped at 30 MB per file, and also subject to a daily limit.

## Citations across formats

An answer in Chat, a Review result or a Discovery cell can cite any indexed file, and clicking the citation opens that file in the viewer. How precisely it lands depends on the preview:

| Source                 | What happens when you click the citation                                                                          |
| ---------------------- | ----------------------------------------------------------------------------------------------------------------- |
| PDF, Word, PowerPoint  | Opens at the cited page with the passage highlighted.                                                             |
| Excel, email, HTML     | Opens with the cited passage highlighted in the rendered view.                                                    |
| Image, plain text      | Opens the file. The passage itself is not highlighted.                                                            |
| Audio, `.msg`, `.tiff` | Opens a tab reading **Preview not available for this file type**, with the file's name and a **Download** button. |

## Tips

<AccordionGroup>
  <Accordion title="Upload originals, not converted versions">
    If you have the original `.docx`, upload that rather than a PDF you exported from it. Libra converts it for preview but keeps the original, so the download stays editable.
  </Accordion>

  <Accordion title="Give scans a moment before you search">
    Scanned PDFs, photographs and `.tiff` files are text-extracted in the background. No hits on a fresh upload usually means extraction is still running, not that the text is missing. Wait, then re-run the query.
  </Accordion>

  <Accordion title="Upload email attachments separately">
    The `.eml` preview shows the message, not its attachments. If the attachment is the document that matters, upload it as its own file so it is indexed, previewable and citable in its own right.
  </Accordion>

  <Accordion title="Use Discovery for data files">
    A folder of spreadsheets is a Discovery's natural input. Rather than paging through each workbook in the viewer, extract the fields you need into a Discovery table.
  </Accordion>

  <Accordion title="Convert what Libra won't take">
    `.svg` and `.bmp` are refused outright, and `.tiff` gives you indexing without a preview. If you need the file on screen as well as in the index, convert it to PNG or PDF before uploading.
  </Accordion>
</AccordionGroup>

<div className="libra-buddy-callout">
  <img src="https://mintcdn.com/libra-4206ec93/wgVZXcGnHS4aJk9T/assets/images/libra-buddy/frustrated.png?fit=max&auto=format&n=wgVZXcGnHS4aJk9T&q=85&s=79cdd5718de4bb8a32512ea72933eda6" alt="Libra mascot frustrated" width="725" height="632" data-path="assets/images/libra-buddy/frustrated.png" />

  <div className="libra-buddy-callout-content">
    Uploaded a mixed batch and came up short? An unsupported type doesn't fail the whole upload — the rest goes through and a notice names what was skipped. Worth reading before you assume everything landed.
  </div>
</div>

## Next steps

<Columns cols={2}>
  <Card title="Folder structure" icon="folder-tree" href="/en/features/documents/folder-structure">
    Organise Project files into folders.
  </Card>

  <Card title="Project files" icon="folder" href="/en/features/documents/library">
    Back to the Project files overview.
  </Card>
</Columns>