A lab accumulates file formats the way it accumulates equipment: one per instrument, one per collaborator, one per journal. Then somebody sends a Visio workflow to a machine with no Visio on it, or an SVG of a molecular diagram that the browser renders as a download prompt.

OnlineDocumentViewer.com opens those in a browser tab. Free, no account, and the file is deleted from the server afterwards.
The formats a lab actually gets stuck on
| File | Viewer | Limit |
|---|---|---|
| SVG diagram, EPS figure, DNG or TIFF plate | Vector and raw image viewer | 25 MB |
| VSD, VSDX workflow from Visio | Visio viewer | 25 MB |
| Multi-page TIFF scan | TIFF viewer | 25 MB |
| Paper or preprint (PDF) | PDF viewer | 25 MB |
| Protocol or manuscript (DOC, DOCX, ODT, RTF) | Word viewer | 15 MB |
| Data table (XLS, XLSX, CSV, ODS) | Excel viewer | 20 MB |
| Correspondence with an attachment (EML, MSG) | Email viewer | 10 MB |
The Visio viewer takes nine extensions — VSD, VSDX, VSS, VSSX, VST, VSTX, VDX, VSX and VSDM — which covers both the diagrams and the stencils a collaborator sends with them.
What it does not do
Be clear about the shape of the tool before you plan a workflow around it:
- No account, no library, no sign-up. There is nowhere to keep a file here. Upload, read, close, gone.
- No editing. It renders. A diagram cannot be annotated, corrected or re-exported.
- No batch upload. One file at a time. No ZIP, no folder, no queue.
- No OCR. Search works on a text layer. A scanned page of a lab notebook is a picture of text, and search returns nothing on it.
- No conversion of these formats. The converters here take PDF, Word, Excel, PowerPoint, CAD, email and common images — not SVG or Visio.
Where the paid product sits
Everything above is the free website. Doconut is the .NET SDK: the same rendering engine, licensed to run inside your own application, on your own servers. If the requirement is that files never leave the institution's network, that is the one to look at — not this website.
Open the viewer hub and pick the page for the format you were sent.