---
title: "Why do I encounter the error 'Javac version is above the compatible version' when I try to run my Catalyst application locally using catalyst serve."
url: https://docs.catalyst.zoho.com/en/faq/cli/cli-javac-incompatible/
description: "Catalyst only supports the versions Java 8, Java 11, Java 17, Java 21, and Java 25 currently. You must therefore ensure that the installed java and javac …"
last_updated: 2026-11-13T05:00:22Z
service: All Services
type: faq
---

Catalyst only supports the versions Java 8, Java 11, Java 17, Java 21, and Java 25 currently. You must therefore ensure that the installed `java` and `javac` versions are 1.8.x, 11.0.x, 17.0.x, 21.0.x, or 25.0.x before you debug a Java function in the CLI.