Requires Ruby or Groovy.
cd Cucumber; ruby gherkin-ide.rb Open gherkin-ide.html
or
cd CucumberJVM; groovy gherkin-ide.groovy > ide.html Open gherkin-ide.html
Open up "gherkin-ide.html" in a browser. Begin typing in the text box. Enter will populate the text area above. You may also paste into the text area.