How to Download and Install Java on Your Computer

Where to get Java and what you're actually downloading

Java comes from Oracle, the company that owns it. You download it from Oracle's website at java.com or oracle.com/java/technologies/downloads. What you're getting is the Java Runtime Environment (JRE) — the software that lets your computer run programs written in Java. Most people need only the JRE, not the full development kit.

Before you download, know that Java is free, but Oracle will ask you to review and accept their license agreement. You're not paying money, but you are agreeing to their terms of use. Read it if you want to, or scroll to the bottom and click "Accept License Agreement" to move forward — most people do the latter.

Java updates regularly. If you already have Java installed, you can check your version by opening your system settings or searching "Java" in your computer's control panel. Keeping Java current matters for security, since older versions can have vulnerabilities that newer ones patch.

Key Takeaways

Download Java from java.com or oracle.com/java/technologies/downloads, not from a third-party site, to avoid bundled software you did not ask for.
Most people need the JRE (Java Runtime Environment), not the JDK (Java Development Kit), unless you are writing Java code yourself.
The download is free, but you must accept Oracle's license agreement before installing.
After installation, Java runs in the background and updates itself, so you do not need to manually check for new versions each time.
If a website or program tells you that you need Java but you are unsure, check your system first — you may already have it.

Steps to download Java on Windows

Go to java.com in your web browser. Click the large "Download Java" button. The page will detect that you are on Windows and offer you the Windows installer. Click the download button next to the version that matches your system — if you do not know whether you have 64-bit or 32-bit Windows, choose 64-bit, since most modern computers use it.

The file will download as an .exe file (something like jre-8u391-windows-x64.exe). Open your Downloads folder, find the file, and double-click it. Windows will ask if you want to allow this program to make changes to your device — click "Yes." The installer will walk you through the rest. You can accept all the default settings and click "Next" until the installation finishes. When it is done, you can delete the .exe file from your Downloads folder — you do not need it anymore.

Java will now run automatically when a program or website needs it. You do not have to open it yourself or do anything else to activate it.

Steps to download Java on Mac

Go to java.com in your web browser. Click "Download Java." The page will detect that you are on Mac and offer you the Mac installer. Click the download button. The file will download as a .dmg file (something like jre-8u391-macos-x64.dmg).

Open your Downloads folder and double-click the .dmg file. A window will open showing a Java icon and an Applications folder. Drag the Java icon into the Applications folder. Mac will copy Java to your system. When it finishes, you can eject the .dmg file (right-click it and select "Eject") and delete it from Downloads.

Java is now installed. Like on Windows, it runs in the background when needed and you do not have to open it manually.

Steps to download Java on Linux

Linux users typically install Java through their system's package manager rather than downloading an installer file. Open your terminal and use the command for your distribution: on Ubuntu or Debian, type sudo apt install default-jre. On Fedora or Red Hat, type sudo dnf install java-latest-openjdk. On Arch, type sudo pacman -S jre-openjdk.

Your system will download and install Java automatically. When it finishes, you can verify the installation by typing java -version in the terminal. If Java is installed, the terminal will show you the version number.

Why you might need the JDK instead of the JRE

The JRE (Java Runtime Environment) runs Java programs. The JDK (Java Development Kit) includes the JRE plus tools for writing and testing Java code. If you are a student learning to code, a developer building Java applications, or someone following a tutorial that specifically asks for the JDK, you need the JDK. If a website or program just says "you need Java," the JRE is what you want.

The JDK is larger and more complex, so do not download it unless you have a specific reason. If you are unsure, start with the JRE. You can always install the JDK later if you need it.

Checking if Java is already installed

You may already have Java on your computer without knowing it. On Windows, open the Control Panel, search for "Java," and click the Java icon if it appears. A window will open showing your installed version. On Mac, open System Preferences, click "Java" if it is there, and you will see your version. On Linux, open a terminal and type java -version.

If Java is installed, the system will tell you the version number. If nothing appears or you get an error, Java is not installed and you should follow the download steps above. If Java is installed but very old (more than a year or two), you can download a newer version using the same steps — the new version will replace the old one.

Staying safe when downloading Java

Only download Java from java.com or oracle.com. Do not download it from other websites, even if they claim to have it. Third-party sites sometimes bundle Java with unwanted software — toolbars, search engines, or other programs you did not ask for. Downloading from Oracle's official site avoids this problem.

After you download Java, you do not need to do anything else to keep it current. Java includes an auto-update feature that checks for new versions in the background and installs them without interrupting your work. You will see a notification when an update is ready, but you do not have to manually search for updates yourself.

Frequently Asked Questions

Do I have to pay for Java?

No. Java is free to download and use. Oracle may ask you to accept their license agreement, but there is no cost involved.

What is the difference between java.com and oracle.com for downloading?

Both are official Oracle sites. java.com is simpler and designed for people who just need to run Java programs. oracle.com/java/technologies/downloads has more options, including the JDK and older versions. For most people, java.com is easier.

Will Java slow down my computer?

Java runs in the background only when a program or website needs it. When nothing is using Java, it takes up almost no resources. It will not noticeably slow down your computer.

Can I uninstall Java if I do not use it?

Yes. On Windows, go to Control Panel and uninstall it like any other program. On Mac, find the Java folder in Applications and drag it to Trash. On Linux, use your package manager to remove it. If a program later tells you it needs Java, you can reinstall it anytime using the same steps.

What if the download fails or the installer will not open?

Try downloading again from java.com. If the file is corrupted, deleting it and re-downloading usually fixes the problem. Make sure you have enough free space on your computer (Java needs less than 200 MB). If you are still stuck, check that your antivirus software is not blocking the installer — temporarily disable it, try again, and turn it back on when done.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.