Minecraft needs Java to run. After Java applets died, most of the remaining Java users were programmers, so a lot of the more recent documentation about how to use Java has shifted towards a programmerish audience. There's a lack of resources for everyday people. This document is an attempt at closing the gap.

Getting Java

I'd like to present four methods of getting Java onto your system, each with their benefits and drawbacks. In order of "easiest but most restrictive" to "more complex but most flexible":

1. Just letting a launcher do it for you

Some launchers automatically provision Java installations, like the official launcher, GDLauncher, Lunar Client if you're in their ecosystem, and such. You can use one of these launchers and never have to think about installing Java.

There are two main drawbacks. First, and most obviously, I hope you like that launcher, because you tie yourself to it. The vanilla launcher in particular is very unfriendly to keeping your Minecraft installations separated, and it's hard to install modloaders into it.

Also, while these launchers let you pick from a few major versions (java 8, java 17, etc), you often can't change the patch version. The current version of Java 8 is Java 8u412, but the vanilla launcher still ships Java 8u51, which is almost ten years old, has bugs, and ships severely outdated SSL certs. Problems caused by this are rare, but if you stumble into one and your launcher doesn't provide the right version, you might need to install Java yourself.

2. Java installers

The easiest way to get Java is to run an installer. By far, the best place to get Java installers is from Eclipse Temurin.

• Select your operating system and architecture. If you're not sure which architecture, pick x64.
• Under "Package Type", select JDK.
• Finally, select the major version of Java you want.
• Download the .msi installer and run it.

This works for a lot of people.

Here's a tip: pick a different folder than C:/Program Files/Java. Old versions of Minecraft need Java 8, newer versions require Java 17, and newer-still versions require Java 21, so if you want to play a variety of modpacks you'll want to have all these installed at the same time. In your Minecraft launcher, make sure to manually set the path to the Java executable as well. (I've heard of people reinstalling Java every time they switch versions - it doesn't have to be this way!)

3. Java zips

You don't really need to install Java to use it. Java is just a collection of files on your computer; in the bin folder you'll find javaw.exe, which is the file your Minecraft launcher runs to start Minecraft.

All installing Java does is add a file-association to your computer (so you can double-click on .jar files to run them) and modify a few environment variables (so you can run java in the command-line). You don't need any of this to play Minecraft. Instead, just manually tell your launcher where to find Java.

Method

Head to the Eclipse Temurin website and get the "zip" instead of the installer.

Benefits

Drawbacks

You won't have the file-association set up system-wide. You won't be able to double-click on a .jar to "run" it.

4. Package managers

Rationale

Why Temurin and not Oracle?

Temurin's website doesn't beg you for passwords or license agreements.

Oracle's JDK and Temurin are both based off the OpenJDK open-source project. Oracle's JDK includes a number of proprietary components, which are not relevant to Minecraft (and frankly not relevant to most people).

Why Temurin and not ____?

There are lots of other builds of Java based on the OpenJDK open-source project:

• You can download directly from OpenJDK. They only provide zips (no installers) and don't provide Java 8.
• You can download from Azul or Amazon or Microsoft or whatever. Their builds differ from OpenJDK mostly in professional support opportunities and other things that aren't really relevant to Minecraft players.
• You can download GraalVM. Good luck with that.

I recommend Temurin because it's "plain", the website is decent, and it's the JDK I use on my personal computers.

Why the JDK, not the JRE?

Java is packaged into a Java Development Kit and a stripped-down Java Runtime Environment. The JDK is a superset of the JRE, and is about four times larger, comtaining a Java compiler and other assorted tools mostly relevant to developing Java programs.

The JRE is fine most of the time, but biting the bullet and downloading the JDK will prevent problems down the road:

• The JDK/JRE distinction dates from the applet days, where the download size mattered a lot more.
• To debug a slow game you might want to use a Java profiler like VisualVM. These need JDK-exclusive features.
• Some (hacky) mods leverage JDK-exclusive features like the Instrumentation API.
• And of course, if you ever get in to writing your own mods you'll need the JDK :)

So this is why I recommend the JDK.