Install JMRI®
A great tool for programming decoders, simplifying the job of configuring DCC decoders from your computer
Design and Operate control panels that reflect the real-time state of your railroad and let you control it
A system for Dispatching, grouping your Roster and Throttles
Build Trains from your Roster and print Train Manifests that detail the work your train crews will perform
A set of tools for using Audio with JMRI
Cool Uses
People have used JMRI to do some great things for the model railroad community.
Our Gallery page highlights some of these.
Also, there are many apps with JMRI connections.
Supported Hardware
Devices, command stations, networks, and protocols:
JMRI Setup and Installation
JMRI environments...

JMRI Help:

Contents Index
Glossary FAQ

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Using Java 11 with JMRI

We recommend using Java 11 with current JMRI versions. JMRI needs a "Java Runtime Environment" (JRE), but will work fine with the larger "Java Development Kit" (JDK).

Before getting a new version of Java, it is useful to check what version is currently installed on your computer. On Windows, for example, open a "command" window by typing "Command prompt" into the search bar next to the Windows Start icon. Then type:

java -version

IT IS RECOMMENDED THAT YOU REMOVE OLD VERSIONS OF JAVA BEFORE YOU UPGRADE. This avoids a number of reported problems. On Windows, for example, you can:

See the JMRI Setup and Install pages for more information.

Getting Java 11

Here are some places you can get Java 11. Click on the links to go to the download page.

For 32-bit or 64-bit computers:

Additionally for 64-bit computers:

Local install option:

Since JMRI 4.99.9

Linux and macOS users can also install Java inside JMRI itself, instead of installing it centrally on their computer. This can be useful if you need different Java versions for other programs, or if for some reason you can't do the central Java install or removal.

We recommend installing Java as described on the top half of this page when possible. The local-install described here is only for cases when that can't be done. Note that you'll need to repeat this process every time you update JMRI, as the local Java install will be overwritten during the update process.


On macOS, the process is:

When you're done, the JMRI folder contents should look like the picture to the right.

You're all set to start JMRI using that local version of Java!


On Linux, the process is:

You're all set to start JMRI using that local version of Java!