OpenAnyFile
What is a .nupkg file?
NuGet Package is an app package format developed by .NET Foundation, first released in 2010. It is usually created by NuGet, dotnet pack.
A ZIP with a .nuspec manifest and per-framework DLLs under lib/.
File details
| Full name | NuGet Package |
|---|---|
| Category | Apps & packages |
| MIME type | application/zip |
| Signature (magic bytes) | 50 4B 03 04 (ZIP) |
| Developer | .NET Foundation |
| Introduced | 2010 |
| Opens with | Archive browser |
| Uploaded? | No — read locally in your browser |
How to open a .nupkg file
OpenAnyFile routes .nupkg files to its archive browser, which shows a folder tree — open any file inside without extracting.
- Drop your .nupkg file on the box above, click it to choose the file, or paste it with Ctrl+V.
- The real format is detected from the file's first bytes — not just its name.
- The file opens in the archive browser.
- Use fullscreen for a closer look, check its checksums, or download it back unchanged.
What works — and what does not
Works
Viewing and inspecting: a folder tree — open any file inside without extracting. Size, type, signature and checksums are always shown.
Does not work
Editing and saving back. OpenAnyFile is a viewer, not an editor — for changes you still need the original app.
Is it safe to open a .nupkg file online?
Here, yes — because nothing is uploaded. Most "online viewers" send your file to their server. OpenAnyFile reads it with your browser's File API and decodes it on your own device, so there is no copy anywhere else. You can check: open your browser's network tab while opening a file — no upload appears.
Questions about .nupkg files
Can I open a .nupkg file without installing software?
Yes. OpenAnyFile opens .nupkg files in your browser using its archive browser. You get a folder tree — open any file inside without extracting, with nothing installed and no account.
How do I know a file is really a .nupkg file?
Check its first bytes instead of its name. A genuine NUPKG file begins with 50 4B 03 04 (ZIP). OpenAnyFile shows the detected type, so a renamed file is easy to spot.
Is my .nupkg file uploaded anywhere?
No. The file is read locally by your browser and never sent to a server — it even works offline once the page has loaded.
Does it work on phones?
Yes — on Android and iPhone, in any modern browser. You can also install OpenAnyFile as an app.
Related formats
Other formats from the same family:
Format facts checked and page updated on September 25, 2026.