The best online Java compiler for students and developers. No installation needed. Supports Java 8, 11, 17, 21. Compile and execute Java code instantly in your browser. 🏫 Trusted by students at IITs, NITs, and 500+ engineering colleges across India Choose Your Java Version Compile Java code with any LTS version — switch anytime Java 8 Compiler Lambda, Streams, Optional — classic LTS for enterprise Java 11 Compiler var keyword, HTTP Client, String methods — modern cloud Java 17 Compiler Records, Sealed Classes, Pattern Matching — recommended Java 21 Compiler Virtual Threads, String Templates — latest LTS Why Students in India Choose JavaCompiler.in Built for the needs of Indian students and developers No Installation Needed Works on college lab computers without admin rights. Perfect for GATE, BCA, MCA, B.Tech students. Works on Mobile Data Optimized for Jio, Airtel, and other Indian mobile networks. Code on any Android or iOS device. Prepare for TCS NQT, Infosys InfyTQ, Wipro, Cognizant placement tests with real Java practice. University Curriculum All programs aligned with the Anna University, AKTU, VTU, JNTUH Java syllabus. Why Use an Online Compiler Instead of Downloading Java? No 500MB JDK Download Skip the heavy JDK download. Our compiler runs Java on the cloud — 0 MB on your device. Works on Any Computer College labs, shared PCs, Chromebooks — works everywhere with a browser. Always Up to Date No version conflicts. Switch between Java 8, 11, 17, 21 with a single dropdown. Share Code with One Link Save your code and share a unique URL with classmates or teachers. Why Choose Our Java Compiler? Everything you need to write, compile, and run Java programs online Compile and run Java code in less than 2 seconds with our optimized servers. Mobile Friendly Code on any device - phone, tablet, or desktop. Fully responsive editor. Save your code to the cloud and share with a unique URL. Access anywhere. No download, no installation, no configuration. Just open and start coding. How to Use Our Java Compiler Get started in 3 simple steps - no signup required Write Your Code Type or paste your Java code in the editor above. Syntax highlighting helps you write error-free code.

Click Compile & Run Press the green "Run" button or use Ctrl+Enter to compile and execute your program. See Output Instantly View the output in the console below. Any errors will be highlighted with line numbers. Popular Java Programs Ready-to-run programs covering all essential Java concepts Hello World Program Fibonacci Series Prime Number Check Palindrome Program Armstrong Number Factorial Calculator Star Pattern Pyramid String Palindrome Simple Calculator Online Compiler vs Desktop IDE See why students prefer our online compiler Learn Java From Scratch 60+ comprehensive tutorials covering basics to advanced topics Variables, data types, operators, input/output, and more fundamentals. If-else, switch, loops, break, continue - master program flow. Classes, objects, inheritance, polymorphism, encapsulation. Frequently Asked Questions Everything you need to know about our online Java compiler An online Java compiler is a web-based tool that lets you write, compile, and execute Java programs directly in your browser without installing any software. It runs Java code on remote servers and displays the output instantly. No! Our online compiler runs Java programs on our servers. You only need a web browser and an internet connection to write and run Java code. We support Java 8, Java 11, Java 17, and Java 21 (LTS versions). You can select your preferred version from the dropdown menu in the compiler. Yes! You can save your code and get a unique URL to share with others. Your code will be stored securely and can be accessed anytime. Yes, our online Java compiler is 100% free. There are no hidden charges, no signup required, and no limitations on the number of programs you can run. Absolutely! Our compiler is fully responsive and works on smartphones and tablets. You can code on any device with a web browser. Our compiler typically compiles and executes Java programs in less than 2 seconds. We use optimized servers to ensure fast execution times. Programs have a maximum execution time of 15 seconds and memory limit of 256MB. Network access and file system operations are restricted for security reasons. Yes, your code is transmitted over HTTPS and executed in isolated containers. We do not store or share your code unless you explicitly save it. Yes! You can use Scanner class or BufferedReader to take input. Enter your input in the "Input" section before running the program. Absolutely! Our compiler is perfect for GATE CSE preparation. Practice Java programs, test algorithms, and verify your solutions instantly. Yes! Students from IITs, NITs, and 500+ engineering colleges across India use JavaCompiler.in for their Java programming assignments and practice. Yes, our compiler is optimized for low bandwidth. It works smoothly on Jio, Airtel, and other mobile data connections common in India. Yes! Many students use our compiler to prepare for placement tests at TCS, Infosys, Wipro, Cognizant, and other IT companies. Yes! Click the moon icon in the compiler toolbar to switch to dark mode. The dark theme is easy on the eyes for long coding sessions. Ready to Start Coding? Join 500K+ students who trust JavaCompiler.in for their Java programming journey.