Java21 vs AEM On Premise (6.5 LTS)?

[tim_funk]

Is java 21 supported for AEM On Premise (6.5 LTS)? I'm seeing conflicting answers.

In the software downloads section where I can fetch the Oracle Java's - I see the following banner (for me the 3rd one)

AEM Support for Oracle Java 17 and 21

Adobe Experience Manager 6.5 LTS now supports JDK 17 and JDK 21. These Oracle JDK versions are also now available for download on Software Distribution.

But when I navigate to the "Technical Requirements [ Last update: April 14, 2025]"

https://experienceleague.adobe.com/en/docs/experience-manager-65/content/implementing/deploying/intr...

It says "Oracle Java™ SE 17 JDK Z: Not supported [1]" -- With no mention of JAVA 21.

Is it possible that I just need to wait for "Service Pack 23 targeted May 22, 2025" 

https://experienceleague.adobe.com/en/docs/experience-manager-release-information/aem-release-update...

[lukasz-m · Accepted solution]

Hi @tim_funk,

AEM 6.5 LTS supports or even requires Java 17. Java 21 supported should be added soon to  AEM 6.5 LTS.

https://experienceleague.adobe.com/en/docs/experience-manager-65-lts/content/implementing/deploying/...

Documentation you refers to is for AEM 6.5 not for AEM 6.5 LTS. LTS version have it's own separate documentation - https://experienceleague.adobe.com/en/docs/experience-manager-65-lts

Regarding SP23 - this will be for AEM 6.5 not for LTS version, and it will not change anything in terms of java support for AEM 6.5. If you want to use Java 17 you have to migrate to AEM 6.5 LTS.

AEM 6.5 LTS will have separate set of SPs

[tim_funk]

AHA ... I hadn't realized 6.5 standard and 6.5LTS were 2 different things. (marketing irony)

[SantoshSai]

Hi @tim_funk,

As per my understanding, as of now, Java 21 is not yet officially supported for AEM 6.5 LTS. While support for Java 21 is expected, there is no public confirmation or official documentation yet stating that it will be available in Service Pack 23 (SP23).

IMO, the Banner in Software Distribution Means:

"AEM 6.5 LTS now supports JDK 17 and JDK 21"

This message is forward-looking and may refer to upcoming support, but it does not confirm current compatibility. Adobe sometimes publishes such banners ahead of formal documentation updates.

According to the Technical Requirements Page says (as of April 14, 2025):

• Oracle Java SE 17 JDK Z: Not supported

• No mention of Java 21

This page reflects the current validated support state, usually aligned with the latest released service pack - which is currently SP22. It only gets updated after a service pack is released and verified.

Hope that helps!

[AmitVishwakarma]

Hi @tim_funk ,

Java 21 support is planned, and the banner you're seeing on the Adobe Software Distribution portal is likely forward-looking. Official support will be available once the appropriate Service Pack (SP) is released — potentially SP23 for AEM 6.5 standard, and a parallel LTS update for AEM 6.5 LTS.

That Banner You Saw?

“AEM 6.5 LTS now supports JDK 17 and JDK 21”

This is not yet reflected in the official technical requirements. It most likely refers to planned or upcoming support that will be made official with the release of:

  - SP23 (targeted for May 22, 2025) — for AEM 6.5 standard

  - LTS Patch Release — separate track for AEM 6.5 LTS users

Until the service pack/patch is released and installed, Java 21 is not considered supported in production.

Regards,
Amit