ECJ (disambiguation)

ECJ is the European Court of Justice, the highest court in the European Union in matters of European Union law.

ECJ may also refer to:

Computing

 * Java Evolutionary Computation Toolkit, a Java-based evolutionary Computation Research System
 * Eclipse Compiler for Java, a Java compiler in the Eclipse framework

Other uses

 * Eclipse ECJ, a very light jet produced by Eclipse Aviation
 * Escuela Complementaria Japonesa de Madrid, a Japanese international school in Madrid
 * Evolutionary Computation Journal, a scientific journal on evolutionary computation