Build your own offline Wikipedia and maps hotspot on a Raspberry Pi

You can build an offline library yourself: a Raspberry Pi that makes its own Wi-Fi network and serves Wikipedia and a street map to every phone in the house. The parts cost about $318 today and the software is free. It takes a few evenings.

We sell a finished one, and we are publishing the build anyway. If you enjoy this kind of project, you should do it. If you get to step four and decide you would rather not, you will know exactly what you are paying us for.

One note on what we have and have not done ourselves. We run this software every day on a Linux server with all outside network access blocked, and everything in "what broke" below happened to us. Our own tests on the Raspberry Pi hardware (the hotspot on real phones, start-up time, how many readers at once) are in progress, so this page gives you the standard steps for the Pi and no performance numbers.

1. The parts

Today's prices for each part are in the parts list.

2. Put the system on the drive

Use the free Raspberry Pi Imager on your computer. Choose Raspberry Pi OS Lite (64-bit), pick the NVMe drive in its USB adapter, and in the settings give the Pi a name, a user and a password, and turn on SSH. Write it, fit the drive in the case, and power on with no memory card in the slot. Current Raspberry Pi 5 firmware starts from the NVMe drive when there is no card.

Connect the Pi to your router with a cable for the setup. You need the internet now so that you never need it later.

3. Download the library and check it

Make a folder and fetch the reader software for 64-bit ARM:

sudo mkdir -p /srv/library && sudo chown $USER /srv/library && cd /srv/library
wget https://download.kiwix.org/release/kiwix-tools/kiwix-tools_linux-aarch64-3.8.2.tar.gz
tar xzf kiwix-tools_linux-aarch64-3.8.2.tar.gz

Then the encyclopedia. The -c matters: it lets the download continue after a stall instead of starting again.

wget -c https://download.kiwix.org/zim/wikipedia/wikipedia_en_all_nopic_2026-06.zim
wget -c https://download.kiwix.org/zim/wikipedia/wikipedia_es_all_nopic_2026-10.zim

English is 49.1 GB and Spanish is 12.4 GB. Every edition and its size is here. Newer files replace these over time, so look in the directory for the current names.

Now check each file against the checksum Kiwix publishes beside it:

wget https://download.kiwix.org/zim/wikipedia/wikipedia_en_all_nopic_2026-06.zim.sha256
sha256sum -c wikipedia_en_all_nopic_2026-06.zim.sha256

It should answer OK. Do not skip this. A damaged 49 GB file can open, look fine, and fail on the one article you need.

4. Serve it

./kiwix-tools_linux-aarch64-3.8.2/kiwix-serve --port 8080 /srv/library/*.zim

From another computer on your network, open http://<the Pi's address>:8080. You should see both encyclopedias and a search box.

To have it start by itself every time the Pi powers on, save this as /etc/systemd/system/library.service:

[Unit]
Description=Offline library
After=network.target

[Service]
ExecStart=/bin/sh -c '/srv/library/kiwix-tools_linux-aarch64-3.8.2/kiwix-serve --port 8080 /srv/library/*.zim'
Restart=always
User=nobody

[Install]
WantedBy=multi-user.target

Then run sudo systemctl enable --now library.

5. Make the Wi-Fi hotspot

Tell the Pi which country it is in, so the radio is allowed to transmit, then create the network:

sudo raspi-config nonint do_wifi_country US
sudo nmcli device wifi hotspot ifname wlan0 ssid HomeLibrary password "choose-a-long-passphrase"
sudo nmcli connection modify Hotspot connection.autoconnect yes

Unplug the network cable. On a phone, join HomeLibrary and open http://10.42.0.1:8080. The phone will warn that this network has no internet. That is the point. Some phones then quietly switch back to mobile data, so tell the phone to stay connected when it asks.

That is a working offline encyclopedia for the whole house. Most people can stop here.

6. Add an offline map

This is the hard part, and it is a separate project.

The map data comes from OpenStreetMap, packaged by Protomaps as one very large world file. You do not download the world. The free pmtiles tool cuts out just your region, straight from the server:

pmtiles extract https://build.protomaps.com/<BUILD>.pmtiles dfw.pmtiles \
  --bbox=-97.62,32.48,-96.46,33.3 --maxzoom=15

Replace <BUILD> with a current build date from the Protomaps downloads page. The four numbers are the west, south, east and north edges of the area. Zoom 15 is street level.

Sizes we measured, so you can plan:

A map file alone shows nothing. You also need a web page that draws it (MapLibre is the usual choice), a web server that can send parts of a file on request, and local copies of the map's fonts and icons. Protomaps publishes the fonts and icons in its basemaps-assets repository. Leave them out and your offline map has roads and no names.

OpenStreetMap's license asks for one thing you must not forget: the words "© OpenStreetMap contributors" on the map.

7. What broke when we built ours

Every one of these happened to us, and each cost an evening.

1. A download mirror went silent for more than a minute and a half. Our job runner decided the download had died and tried to start it again while it was still running. Big downloads need patience built in, and one downloader at a time.
2. One bad answer from the map server ruined a whole extract. A single "502" error in the middle of cutting a map made the tool give up. It needs to retry.
3. The fonts-and-icons archive contained symbolic links. Our unpacker refuses those for safety, so the build stopped. We now unpack only the files we chose.
4. The search count came back as "3,106", with a comma. Our code expected a number and choked. If you script against kiwix-serve, expect formatted text.
5. A Spanish search missed the English article. "Monóxido de carbono" and "carbon monoxide" are the same question in a two-language house. We had to add a glossary so one search asks both.
6. The "find my location" button cannot work. Browsers only share location with secure (https) sites, and a box on your own Wi-Fi is plain http. Offer a pin, coordinates and place search instead.
7. There is no kiwix-serve for Windows in this release. If you want the same library on a Windows laptop, the encyclopedia has to open in the Kiwix desktop app.

What you have at the end

A box that makes its own Wi-Fi and serves two complete encyclopedias, and a map if you did step six. What it does not have yet is one search across everything, a check that every file is intact each time it starts, a safe way to update, or anyone to ask when it stops working. Those are the parts we spent our time on.