To be able to generate some diagrams, you must have Graphviz software installed on your machine.

Important note about version

PlantUML should be working with any version of Graphviz, starting with 2.26.3

The following version have been tested, and are known to work:

  • 2.26.3
  • 2.28
  • 2.30.1
  • 2.34
  • 2.36
  • 2.38
However, it is possible that some cases with some versions have issues.

If you find something wrong, thanks for sending us a note or posting a message on the question&answer page.


By default, the dot executable should be:
  • Windows :
    • Firstly in: c:\Program Files\Graphviz*\bin\dot.exe
    • Then in: c:\Program Files (x86)\Graphviz*\bin\dot.exe
  • On Linux/Mac OS-X :
    • Firstly in: /usr/local/bin/dot
    • Then in: /usr/bin/dot


To have information about where PlantUML is expecting to find dot, you can use the command line:

java -jar plantuml.jar -testdot
You can also use this special diagram description:
test your graphviz dot installation

Environment variable

If you have installed somewhere else Graphviz, you will have to define the environment variable GRAPHVIZ_DOT to the exact location of the dot program. Be carefull, the variable must contain an executable, not a directory.

On Windows

Click on:
My Computer/Properties/Advanced/Environment Variables

Create GRAPHVIZ_DOT to your executable.
For example: d:\example\dot.exe

On Linux/Mac OS-X

setenv GRAPHVIZ_DOT /usr/local/bin/graphviz/dot


You can also define it as a Java Property, by changing some configuration file, or using the -D flag in your java command line.

Command line

Another option is to use the -graphvizdot flag in the command line:
java -jar plantuml.jar -graphvizdot "d:/dummy/dot.exe" file1 "c:/directory2"


You can also change the path of the dot executable in the Ant task:
<project name="OwnTaskExample" default="main" basedir=".">
  <!-- task definition -->
  <taskdef name="plantuml" classname="net.sourceforge.plantuml.ant.PlantumlTask" classpath="plantuml.jar" />

  <!-- process ./src files -->
  <target name="main">
    <plantuml dir="./src" graphvizDot="/path/dot" />

Testing Graphviz

You should use the lastest version of Graphviz to generate your diagram.
Older version (older than 2.26.3 like for example 2.16) may not work. If you want to test your version, you can download dottest.txt and stereo.png and type the following command:
dot -Tpng -otest.png dottest.txt
If an image is correctly generated, it means that your Graphviz/dot installation is fine.