Skip to content
Zero dependency, small footprint, cross-platform I2P Java Router with simple tunnel/socks controller and SAM interface
Java Shell Other
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.
bin apache-ant-1.10.7 upgrade Sep 7, 2019 only attempt to open tunnels once the router is ready and running, to… Aug 24, 2019
org.getmonero.util.normalizeZip normalizeZip now uses specified timestamp, since git will not propaga… Jun 30, 2019
.gitignore build tar.bz2 files instead of zip files for linux/mac Mar 23, 2019
LICENSE LICENSE updated Jan 29, 2019 v1.12 third release fix due to to tunnelcontrol bug Sep 7, 2019
i2p-zero.iml root module file Feb 1, 2019
i2p-zero.png logo added Jan 16, 2019 Update Sep 8, 2019
screenshot1.png added new screenshots Feb 4, 2019
screenshot2.png added new screenshots Feb 4, 2019
screenshot3.png screenshot update Feb 4, 2019

Zero dependency, small footprint, cross-platform I2P Java Router with GUI, simple tunnel/socks controller and SAM interface

Note that I2P-zero is not a re-implementation of I2P. It uses the exact I2P source code from the official I2P GitHub repository.

I2P-zero is a build script that produces a zero-dependency installation of the official I2P release, and includes a simplified front end interface.

This project will run under Linux, and build native launchers for Linux, MacOS and Windows. The launchers will include the I2P router, a SAM listener, simple tunnel and socks tunnel functionality and a minimal JVM.


Download the latest binary releases for Mac/Windows/Linux here:

GUI Screenshots


The zero-dependency distribution sizes are as follows:

OS Uncompressed size (MB) Compressed size (MB) v1.12 Reproducible build SHA-256
Mac 39.2 26.2 989f32326f492310d17c346680423e8f1d9e87f20890fa0a50cd82003af59d7e
Windows 40.2 29.1 aa16c23c6fe03f76c947010d23fcd832323e1a40e938e417ec9e184e38132134
Linux 50.8 32.8 00816c4008f0c6a7d2b40367a73df6025d377cd55a4aff4487b3cc7e9236f729
Mac GUI 61.5 45.1 64f21c35440a38ee3fbc2edcf861fbfcdf4490f9ce7344cb59dac422308e11b4
Windows GUI 62.6 47.4 3c505268fd26d8adec20989b319ff3fbd734d6aec073cbc6b2acfe59ac592b7f
Linux GUI 76.1 52.9 87fadcf0d5034b6a3b3dc8e16236d8b482f7ff5cb0f193266b7a7883a50667ce

Note: Reproducible builds are currently experimental. Due to JDK differences, Builds on Mac will consistently have different hashes than builds on Linux. Official releases will always be built on Linux (Ubuntu).

Building the launchers

All binary releases for Windows, Mac and Linux can be built from either Linux or Mac.

From a freshly installed Ubuntu system, first ensure git is installed:

sudo apt install git

Then, retrieve this project from git:

git clone

Note that the current version of this script uses jdk-12. If this version of Java becomes no longer available for download, then update the references in to the later version. To locate a recent JDK download URL, see

Also note that JDKs for Linux, MacOS and Windows will be downloaded, which will total several hundred megabytes. You may need to ensure your system has zip, unzip and bzip2 installed to run the build script.

Run the bin/ script, which will in turn call the following scripts:

  1. bin/ to retrieve the I2P Java sources, OpenJDK and the Ant build tool

  2. bin/ to build the I2P project retrieved from the I2P repository

  3. bin/ to convert the I2P JARs to modules, compile the Java source code in this project, and then use the jlink tool to build zero-dependency platform-specific launchers.

  4. bin/ to produce the distribution zip files and display their SHA-256 hashes. Note that reproducible builds are currently a work in progress, and that only builds on Linux will show the same hashes as the official releases.

Running the GUI

To run the Linux router, double-click the app located at dist/linux-gui/router/i2p-zero

To run the MacOS router, double-click the app located at dist/mac-gui/router/

For Windows, double-click the app located at dist/windows-gui/router/i2p-zero.exe

Running the command line version

To run the Linux router, type:


To run the MacOS router, type:


For Windows, run:


If it launches successfully, you'll see the message:

I2P router launched.
Press Ctrl-C to gracefully shut down the router (or send the SIGINT signal to the process).

Tunnel control

Note that it may take a short while for new tunnels to be set up.

Call the dist/linux/router/bin/ script as follows to create and destroy tunnels:

Get the router reachability status. Returns a string such as "Testing", "Firewalled", "Running", "Error" router.reachability

Find out if the router is running (where "running" means it has warmed up and is allowing I2P connections to be created). Returns "true" or "false" router.isRunning

Listen for I2P connections and forward them to the specified host and port. Returns the I2P base 32 destination address for the server tunnel created.

Optionally, specify a directory for storing/reading the server key file. If the directory doesn't exist with a file named *.b32.i2p.keys in it, returns a newly created destination address and writes the secret key for the new address to a file called .keys in the specified directory. Otherwise, read the existing secret key from that directory. The server tunnel will listen for I2P connections and forward them to the specified host and port. Note that the base 32 I2P destination address deterministically depends on the contents of the .keys file). server.create <host> <port> <(optional) directory>

or, if you would like a vanity b32 address for your server tunnel that begins with a 3 character (alphanumeric) prefix, type: server.create.vanity <host> <port> <directory> <prefix>

If you do not want to specify the directory parameter above, specify none as the directory. Note that this command may take several minutes to complete.

Check the state of a tunnel. Returns "opening" or "open" server.state <base 32 I2P address> client.state <local port> http.state <local port> socks.state <local port>

Close the tunnel listening for connections on the specified I2P destination address. Returns "OK". server.destroy <base 32 I2P address>

Create a tunnel that listens for connections on localhost on the specified port and forwards connections over I2P to the specified destination public key. client.create <I2P destination> <local port>

Close the tunnel listening for connections on the specified port. Returns "OK". client.destroy <local port>

Create an http proxy (for accessing .i2p web sites), listening on the specified port http.create <local port>

Destroy the http proxy listening on the specified port http.destroy <local port>

Create a socks tunnel, listening on the specified port socks.create <local port>

Destroy the socks tunnel listening on the specified port socks.destroy <local port>

Destroy all tunnels. Returns "OK" all.destroy

List all tunnels. Returns JSON string containing information about all tunnels currently in existence all.list

Start a SAM listener on port 7656. Returns "OK" sam.create

Get the external port randomly assigned to this router when first run, which the firewall should allow incoming UDP and TCP connections on. Returns the port number. router.externalPort

Set the bandwidth limit, measured in KBps. Returns "OK". router.setBandwidthLimitKBps <KBps>

Get the bandwidth limit, measured in KBps router.getBandwidthLimitKBps

Get bandwidth statistics. Returns a comma separated list of statistics router.getBandwidthStats

example response:


or, for pleasant viewing on the command line, automatically updating every 2 seconds:

watch " router.getBandwidthStats | tr ',' '\n' | sort"

Get the I2P-zero version version

example response:

i2p-zero 1.8

Watch the I2P log for messages

tail -f dist/linux/router/i2p.config/wrapper.log

Note on bundled windows wrapper.exe executable

There is a bundled resources/wrapper.exe file in the source tree. This allows the windows distributable to be built even on a non-windows platform.

This file can be deterministically recreated by downloading javapackager from, unzipping it, unzipping the jar file within that, and obtaining the jdk/packager/internal/resources/windows/papplauncher.exe file.

Then, on Windows, download Resource Hacker version 5.1.7 from and use it to add the resources/icons.ico file to the papplauncher.exe file. Finally, verify that the resulting file is identical to the bundled resources/wrapper.exe file.

The sha256 checksum of the file should be 50c9286b9da7a91b8715de3cbcd141ec44eb199642562f43ce82351609115e06

You can’t perform that action at this time.