OnlineDocumentViewer.com and Doconut.com are two products from the same rendering engine, and they get confused constantly. One is a free public website; the other is a .NET library you license and install. Here is the difference, item by item.
What the free site does, and where it stops
OnlineDocumentViewer.com is a public website. Upload a file, read it, and it is deleted when the session ends. Free, no account, 73 extensions across seventeen viewers, plus twenty-two conversion pages. It is not embeddable, it has no API, and there is no paid tier on it.
What the .NET library is
Doconut is the licensed product: a .NET document viewing library you install on your own servers and call from your own application. Documents stay inside your infrastructure and no data goes to Doconut servers.
That distinction is the whole point of this post. The website answers "I cannot open this file". The library answers "my users need to read files inside my product, under my permissions".
The catalogue, and the plugins
The SDK renders 75 extensions across 18 families. The free site accepts 73 of them — the two missing are .dcm and .ima, DICOM, which is one of four separately licensed plugins:
- Annotation
- Converter
- DICOM
- Search
Controlled printing is not on that list because it is not a plugin: it is a capability of the viewer, configured in your integration.
CAD
The free CAD viewer opens DWG, DXF and DGN up to 10 MB, with layer control and measurement, and the CAD converter exports DWG and DXF to PDF up to 5 MB. One file at a time, from a browser.
Inside your own application, the same rendering runs against files your system already holds — a drawing archive, a project database, a storage bucket — with no upload step and no ceiling imposed by a public form. If you need to process a thousand drawings, you call the library a thousand times from your own code. That is what a library is; the website has no equivalent, and no queue.
Get started
Read Doconut.com for the library, its plugins and its licensing. Use OnlineDocumentViewer.com when you just want a file open now.