Accessing Calibre from Anywhere Using Cloudflare Tunnel

Calibre has a “Content Server” feature. User can visit its Content Server via http://localhost:8080 if Calibre is running with content server is turned on by default. However, the content server is only accessible within the same WiFi network, meaning that you cannot read ebooks with mobile device outside home network.

Cloudflare Tunnel makes your Calibre Content Server accessible from anywhere by tunnelling a public domain traffic to the server that runs on your machine locally, if you have a custom domain.

Assumptions

#

1. you own a domain myhost.com and it’s managed by Cloudflare.
2. you are about to create a subdomain calibre.myhost.com for tunnelling public traffic.
3. the tunnel you are about to create is Calibre.

Sign in to the dashboard https://dash.cloudflare.com. Choose Networking > Tunnel at the left menu. Click + Create Tunnel:

Name your tunnel (case-sensitive), then click Create Tunnel:

Follow the instruction to set up tunnel service on your machine. For me as a Mac user, I install cloudflared via homebrew:

brew install cloudflared

Then, you need sudo and type your password to install the service:

sudo cloudflared service install <the token>

If you want to run cloudflared manually (a foreground process):

cloudflared tunnel run --token <the token>

You should see a “Tunnel connected successfully” message if connection is established. Click Continue

Login to Cloudflare in cloudflared

❯ cloudflared tunnel login
A browser window should have opened at the following URL:

https://dash.cloudflare.com/argotunnel?aud=&callback=xxx

If the browser failed to open, please visit the URL above directly in your browser.
2026-06-28T19:44:10Z INF You have successfully logged in.
If you wish to copy your credentials to a server, they have been saved to:
/Users/<your-user-name>/.cloudflared/cert.pem

Find out the tunnel id:

❯ cloudflared tunnel list
You can obtain more detailed information for each tunnel with `cloudflared tunnel info <name/uuid>`
ID                                   NAME    CREATED              CONNECTIONS
<tunnel-uuid> Calibre 2026-06-28T19:32:41Z

You can see the CONNECTIONS is empty, meaning that this tunnel is not running yet.

Create a config file:

❯ sudo mkdir -p /etc/cloudflared
sudo touch /etc/cloudflared/config.yml

In the config.yml file:

tunnel: <tunnel-uuid>
credentials-file: /etc/cloudflared/<tunnel-uuid>.json

ingress:

  - hostname: https://calibre.myhost.com
    service: http://localhost:8080
  - service: http_status:404

Create the tunnel json file:

cloudflared tunnel token --cred-file ~/.cloudflared/<tunnel-uuid>.json Calibre
sudo cp ~/.cloudflared/<tunnel-uuid>.json /etc/cloudflared/

Restart the service:

sudo cloudflared service uninstall 
sudo cloudflared service install 

Modify the plist file /Library/LaunchDaemons/com.cloudflare.cloudflared.plist, add tunnel and run to the ProgramArguments array:

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">
<dict>
	<key>Label</key>
	<string>com.cloudflare.cloudflared</string>
	<key>ProgramArguments</key>
		<array>
			<string>/opt/homebrew/bin/cloudflared</string>
			<string>tunnel</string>
			<string>run</string>
		</array>
	<key>RunAtLoad</key>
	<true/>
	<key>StandardOutPath</key>
	<string>/Library/Logs/com.cloudflare.cloudflared.out.log</string>
	<key>StandardErrorPath</key>
	<string>/Library/Logs/com.cloudflare.cloudflared.err.log</string>
	<key>KeepAlive</key>
	<dict>
		<key>SuccessfulExit</key>
		<false/>
	</dict>
	<key>ThrottleInterval</key>
	<integer>5</integer>
</dict>
</plist>

Add DNS record click "+ add route:

choose published application:

fill in the subdomain (calibre) and service URL (http://localhost:8080) You should see a “Route added successfully” message

Then, visit https://calibre.myhost.com and you should see Calibre’s content server.