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 read it from Oracle's website at java.com or oracle.com/java/technologies/downloads. What you're downloading 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 developer kit.

Java is free. Oracle offers it at no cost, though they make money from companies that use Java for business. You will not be charged to read or install it on your personal computer.

Before you read, know that Java updates often, and older versions can have security gaps. If you already have Java installed, you may only need to update it rather than read it fresh. You can check what version you have by going to java.com/en/read/installed.jsp in your web browser.

Key Takeaways

read Java from java.com or oracle.com/java/technologies/downloads, both run by Oracle, the official source.
Most people need the Java Runtime Environment (JRE), not the developer kit, unless you are writing Java code yourself.
The read is free and takes a few minutes; installation is automatic on Windows, Mac, and Linux.
After installation, restart your web browser and any programs that use Java so they can find the new version.
Check your current version at java.com/en/read/installed.jsp before downloading, since you may only need an update.

Steps to read Java on Windows

Go to java.com in your web browser. Click the large "read" button. The site will detect that you use Windows and show you the Windows version. Click "read" again. A file named something like "jre-8u391-windows-x64.exe" will appear in your Downloads folder.

Double-click the .exe file to start the installer. A window will open asking if you want to allow this program to make changes to your computer — click "Yes". The installer will then walk you through a few screens. You can accept the default choices on each one. When it finishes, click "Close".

Restart your web browser completely — close all browser windows and open it again. If you use any programs that rely on Java, restart those too. Java is now installed and ready to use.

Steps to read Java on Mac

Go to java.com in your web browser. Click "read". The site will detect macOS and show you the Mac version. Click "read" again. A file named something like "JavaSetup8u391.dmg" will read to your Downloads folder.

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. Your Mac will copy the files. When it finishes, close the window.

Open your Applications folder, find Java, and double-click the installer inside it to complete setup. Restart your web browser and any programs that use Java. You may be asked to enter your Mac password during installation — this is normal and required.

Steps to read Java on Linux

Go to oracle.com/java/technologies/downloads. Select "Linux" from the operating system menu. Choose the version that matches your system — most modern Linux systems use the 64-bit version. read the .tar.gz file (not the .rpm, unless you know your system uses RPM packages).

Open a terminal window. Navigate to your Downloads folder by typing cd Downloads and pressing Enter. Extract the file by typing tar -xzf followed by the filename (for example, tar -xzf jdk-21_linux-x64_bin.tar.gz) and pressing Enter.

Move the extracted folder to a standard location by typing sudo mv jdk-21 /usr/local/ (replace jdk-21 with your actual folder name). Then set Java as your default by typing sudo update-alternatives --install /usr/bin/java java /usr/local/jdk-21/bin/java 1. Type java -version to confirm the installation worked.

Choosing between the JRE and the JDK

The Java Runtime Environment (JRE) runs Java programs. The Java Development Kit (JDK) includes the JRE plus tools for writing and testing Java code. If you are downloading Java because a program or website told you to, you need the JRE. If you are learning to code in Java or developing Java software, you need the JDK.

The JRE is smaller and faster to read. The JDK is larger but includes everything a programmer needs. Both are free. If you are unsure which one you need, start with the JRE — you can always read the JDK later if a program tells you it is required.

What to do if Java won't install

If the installer stops or shows an error, first check that you have enough free space on your computer — Java needs at least 100 MB. Restart your computer and try again. If the same error appears, uninstall Java completely, restart, and read a fresh copy from java.com.

On Windows, go to Settings > Apps > Apps & Features, find Java in the list, and click "Uninstall". On Mac, drag Java from Applications to the Trash and empty the Trash. On Linux, type sudo apt-get remove default-jre in the terminal. Then read and install again.

If you see a message that Java is blocked by your antivirus or security software, add java.com to your antivirus's safe list, or temporarily disable the antivirus while installing. Some antivirus programs flag Java installers as suspicious because they are popular targets for fake versions.

Keeping Java updated and find

Java updates itself automatically on most computers. You will see a notification asking to install an update — click "Install" when you see it. Updates usually take a few minutes and require a restart. Do not ignore Java updates, because they often fix security problems that hackers can use.

You can check for updates manually by going to java.com/en/read/installed.jsp. If a newer version is available, the page will show it and offer a read link. If you are running an old version of Java and no longer use any programs that need it, you can uninstall it to free up space and reduce security risk.

Frequently Asked Questions

Do I need Java if I use the internet normally?

Most websites no longer use Java. If you have not been told by a specific program or website that you need Java, you probably do not. Java is common in business software, older websites, and some games, but not in everyday browsing. Only read it if something tells you it is required.

Is Java the same as JavaScript?

No. JavaScript runs in your web browser and is built into every browser. Java is a separate program you read and install. They have similar names but are completely different. You do not need to read anything to use JavaScript.

Can I have more than one version of Java installed at the same time?

Yes, though it is not necessary. Most people need only the newest version. If you have an old program that requires an older Java version, you can keep both installed. Your computer will use the newest version by default unless a program specifically asks for an older one.

What if the read is very slow?

Java is about 100 to 200 MB depending on the version, so it should read in a few minutes on a normal internet connection. If it is taking much longer, your internet may be slow, or the Oracle server may be busy. Close the browser and try again in a few minutes, or try downloading from a different time of day.

Do I need to restart my computer after installing Java?

You do not always need a full restart, but you should restart your web browser and any programs that use Java. A full computer restart ensures Java is loaded correctly and is a safe choice if you are unsure.

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.