You can find Tomcat and java version running on Linux either by executing the org.apache.catalina.util.ServerInfo class from catalina.jar or by executing version.sh shell script. The first solution will work on any operating system including Windows and UNIX because it's using a Java class from a catalina.jar file, which is platform independent. Though, if you don't know how to run a class from JAR file, you can check the steps here. Alternatively, you also have a version.bat file inside tomcat/bin directory to check the version of Tomcat in Windows. When you run this script in Linux or Windows it prints information about tomcat version, the java version used to run tomcat, Server built date, OS name, OS Version, architecture, JVM version and JVM vendor etc.