Is There an Inkscape Online Version?
The direct answer
Inkscape is a desktop application. The project does not publish an official browser-based edition, and any site offering "Inkscape online" is either running something else entirely or repackaging the installer. If you need Inkscape itself, download the Windows build — it installs in a couple of minutes and costs nothing.
Why people search for it
Usually one of three reasons: a locked-down school or work computer, a Chromebook, or a single quick edit that does not feel worth an install. Each has a different sensible answer.
When you cannot install software
Use the portable route: the 7z archive unpacks into a folder and runs without registering anything with Windows, which is often permitted where installers are not. Instructions are under portable and side-by-side installs. Where nothing at all can run locally, a browser SVG editor will handle simple shape and text edits, though it will not match Inkscape's node editing, path effects or extensions.
On a Chromebook
Inkscape runs on Linux, so machines with the Linux (Crostini) environment enabled can install the Linux build or the Flatpak. It is slower than a Windows desktop on the same class of hardware, but it is the real program rather than a substitute.
For one quick change
Editing an SVG's color or text can be done in a plain text editor: SVG is XML, and fills appear as readable attributes. That is genuinely the fastest fix for "make this icon blue." For anything involving geometry, install the editor — reshaping curves by hand-editing coordinates is not a good use of an afternoon. Background on the format is in working with SVG.
What you give up in a browser tool
Node-level path editing, boolean operations, Live Path Effects, the bitmap tracer, mesh gradients, the XML editor, Python extensions, precise print export and offline work. For hobby projects an online editor may be enough; for cut files, sublimation artwork or client work, the desktop program is the practical tool.
Questions people ask
Is there an official Inkscape web app?
No. Inkscape is distributed as a desktop application for Windows, macOS and Linux. There is no official browser version.