Most online viewers are one upload box that tries to render anything. Doconut.app is seventeen separate viewers, and the split is the point: a CAD drawing needs layers you can switch off, an email needs its headers shown, and a spreadsheet needs you warned that nothing has been recalculated. A single generic viewer does none of that.

Why Choose Doconut.app?

Wide Format Support

Seventy-plus extensions in total:

Documents: PDF (25 MB), DOC, DOCX, ODT, RTF (15 MB)
Spreadsheets: XLS, XLSX, CSV, ODS (20 MB)
Presentations: PPT, PPTX, ODP (20 MB)
Images: PSD (25 MB), SVG, TIFF, DNG, EPS (25 MB)
CAD: DWG, DXF, DGN (10 MB)
eBooks: EPUB (25 MB)
Email: EML, MSG, EMLX (10 MB)
Diagrams and plans: Visio (25 MB), Project (20 MB)

Not DICOM: .dcm and .ima are deliberately excluded from the free viewers.

User-Friendly Interface

Every viewer gives you page navigation, zoom, fit-to-window and printing with Ctrl+P. What differs is what each one knows about its format:

The CAD viewer draws from the geometry rather than the embedded preview, lets you switch layers off, and measures distances and areas.
The email viewer shows From, To, Date, Message-ID and the Received lines, and lists attachments separately.
The vector and raw viewer applies embedded ICC profiles and shows a photograph's EXIF beside it.
The PSD viewer renders the saved composite, so you do not need the designer's fonts.
The Excel viewer shows stored values, because a viewer does not recalculate.

No Installations or Downloads Required

With Doconut.app, there’s no need to worry about cumbersome installations or restricted access. You upload one file, read it, and close the tab — no install, and nothing to set up first.

What happens to your file

Documents are deleted from our servers when the viewing session ends, and the upload runs over HTTPS. There is no account, so nothing is stored under your name.

We hold no ISO 27001, SOC 2 or HIPAA certification, and we are not offering encrypted storage — because we are not offering storage.

Cross-Device Compatibility

Because rendering happens on our servers, the same pages arrive on a phone, a tablet or a desktop, and an underpowered machine is not a disadvantage. What you still need is the bandwidth to upload the file in the first place.

What none of them do

The specialisation runs one way only. No viewer here converts a file, edits it, annotates it or signs it, and none accepts more than one file at a time. Conversion is the sibling site OnlineDocumentViewer.com; embedding any of this in your own application is the Doconut SDK.

Free to Use

One of the most appealing aspects of Doconut.app is that it remains entirely free of charge. Users can enjoy access to its powerful features without hidden fees or subscriptions, making it accessible to all.

Specialized Viewers for Different File Types

The practical benefit of the split is the error message. Because each viewer knows its own extensions and its own ceiling, a file that will not work is refused at upload with the specific reason — the format is wrong for this page, or it is over the 10 MB CAD limit — instead of failing silently halfway through a render.

Key Takeaways

Seventeen viewers, each specialised for its format family.
70+ extensions, with the size ceiling set per format rather than per site.
Nothing installed, no account, and the file deleted when you close the tab.
Free, with no paid tier.
Viewing only — no conversion, no editing, no batch.

Start at the page for your format, or drop the file on the home page and let it choose.