What Kiwix does
Kiwix is an offline reader for web content, built mainly to make Wikipedia available offline. It reads archives in ZIM format, a highly compressed open format with extra metadata. The desktop version is a viewer and manager of ZIM files for recent GNU/Linux and for Windows 10 and 11.
Think of a ZIM file as a sealed website in a box. The reader opens it in a browser-like window, so articles, infoboxes and internal links behave much as they do online. That is a big step up from a folder of saved HTML pages or PDFs.
The author's setup
Afolabi's account is first-person, and I haven't reproduced his testing. Here is what he reports:
- Install: His Windows build came as a ZIP. He extracted it and launched
kiwix-desktop.exe. - Destination: In Settings he pointed the download directory at his USB drive, F:. Downloaded ZIM files landed directly on the stick and showed up under Local Files.
- Catalog: The built-in catalog filters by language, category and content type.
- Size reality check: The catalog offered a full English Wikipedia without pictures at 49.07GB and one with pictures at 118.67GB. Neither fits on 16GB, so he picked "Wikipedia 100" at 317.98MB and a 12.55MB Project Gutenberg collection.
- Offline test: With Wi-Fi off, both collections still opened. Wikipedia 100 kept its formatting, images, infoboxes and working links. The Gutenberg ZIM opened with its own catalog, and he read an English-German business dictionary from it.
Picking the right Wikipedia edition
Kiwix's FAQ says each Wikipedia file comes in three flavours:
| Flavour | Contents | Space vs. full |
|---|---|---|
| mini | Article introductions plus the infobox | Saves about 95% |
| nopic | Full articles, no images | About 75% smaller |
| maxi | The default full version | Baseline |
Two caveats:
- Percentages are approximate. They are Kiwix's own figures, not guaranteed file sizes.
- Sizes change with each release. Kiwix's public download directory lists
wikipedia_en_100_2026-08.zimat 318M. It also lists an English full maxi archive at 115G for February 2026. The article's 118.67GB figure is consistent with that range, though I couldn't match it to an exact catalog entry. Check the date and size shown before you download.
"Wikipedia 100" is a curated subset, not a trimmed copy of everything. It suits a small stick, but it won't answer obscure questions.
Before you plug in: filesystem and capacity
This is the practical gap in the original story. It never says how the stick was formatted.
Kiwix's JS client documentation warns that on older devices, archives over 2GB may not be supported on FAT-formatted storage. Wikipedia's Kiwix entry notes that all of English Wikipedia with pictures fits on a large USB stick or external media. The same Kiwix help text says FAT16 is limited to under 2GiB per file and FAT32 to under 4GiB. It says exFAT and other modern filesystems such as NTFS don't have the problem.
That text describes a different Kiwix client, so treat it as general guidance rather than a Windows Desktop rule. Still, if you plan to carry anything bigger than a few hundred megabytes, check the format first. In Windows, right-click the drive in File Explorer and choose Properties, and the filesystem is listed on the General tab. Reformatting erases the drive, so copy off anything you want to keep.
A "16GB" stick also formats to somewhat less usable space. Leave headroom for the archives and anything else you carry.
Reader on the PC, or reader on the stick?
The author kept the reader installed on Windows and only the library on the drive. Kiwix says it also offers portable versions, and its download options list portable builds for Windows 10/11. Its FAQ lists the Microsoft Store, Winget and a standalone installer as Windows install routes.
A fully portable setup means the app travels with the library. Kiwix's GitHub wiki describes it for Kiwix 2.4.0 on Windows and Linux. The steps are to download Kiwix, unpack it, create a .portable file, and start Kiwix. The wiki adds that you can add ZIM files by downloading them in Kiwix or by placing them in the data directory by hand, and either way they appear in your local library.
Pick based on how you work:
- Your own PC only: Install Kiwix locally and keep only the ZIM files on the stick, as the author did.
- Borrowed or locked-down machines: A portable build on the drive is worth trying. Whether it runs there depends on that machine's policies, which I haven't tested.
Maintenance: it's a snapshot
An offline archive doesn't refresh itself. As Wikipedia's Kiwix entry puts it, archived content can no longer be edited. Kiwix's FAQ states that incremental ZIM updates aren't currently available, though the feature is being explored. To get newer content, download a newer release and replace the old file.
The directory listings show how often that happens. Many Wikipedia archives have releases a few months apart. Don't treat a ZIM as current for breaking news or fast-moving technical topics.
What else fits on the stick
The author mentions programming documentation, Project Euler, Stack Overflow material and TED collections. Kiwix's catalog page also highlights freeCodeCamp's JavaScript curriculum, DevDocs, iFixit repair guides, Ready.gov emergency guidance and MedlinePlus. For IT readers, DevDocs and the iFixit guides look like the most useful extras. I haven't verified how well any of them render in the desktop app.
Bottom line
For a few hundred megabytes, a spare USB stick becomes a searchable, browsable reference library that works with no network. The caveats are the ones above. Choose the edition that fits your drive, check the filesystem, treat the contents as a dated snapshot, and test it with networking off before you rely on it.