JavaScript Console
Write and execute JavaScript code in real-time. Press Enter to run single lines or Shift+Enter for multi-line code.
Console output will appear here...
About JavaScript Console
A simple JavaScript REPL (Read-Eval-Print Loop) that executes your code in the browser. Use console.log(), console.error(), console.warn(), and console.info() to output values. The return value of your code is also displayed. Note: Code runs in a sandboxed environment with limited access to browser APIs.
How to Use
- Type or paste JavaScript code in the input area
- Press Enter to execute the code (or Shift+Enter for new line)
- View the output, including console.log statements and return values
- Use the up/down arrow keys to navigate command history
- Click "Clear" to reset the console output
- Variables persist between executions within the same session
Features
Real-time Execution
Execute JavaScript code instantly and see results immediately without any setup or compilation required.
Console Output
Full support for console.log, console.warn, console.error, and other console methods with proper formatting.
Command History
Navigate through previous commands using arrow keys, making it easy to re-run or modify earlier code.
Persistent Variables
Variables and functions defined in one execution persist for subsequent commands within the same session.
Common Use Cases
- Quick Testing: Test small JavaScript snippets without setting up a project
- Learning: Practice JavaScript concepts and experiment with code
- Debugging: Isolate and test specific functions or logic
- Prototyping: Quickly prototype algorithms or data transformations
- API Exploration: Test JavaScript built-in methods and APIs
- Interviews: Practice coding challenges in a real JavaScript environment
Frequently Asked Questions
What is JavaScript Console?
Online JavaScript REPL/console for testing and running code snippets. It provides an interactive environment similar to browser developer tools or Node.js REPL, perfect for quick testing and experimentation.
What JavaScript features are supported?
The console supports modern JavaScript (ES6+) including arrow functions, destructuring, async/await, classes, modules, and all standard built-in objects. It runs in your browser's JavaScript engine.
Can I access the DOM or browser APIs?
The console runs in a sandboxed environment for security, so direct DOM manipulation is limited. However, you can test pure JavaScript code, data structures, algorithms, and most built-in JavaScript methods.
Is my code saved or shared?
No, your code is never saved or sent to any server. Everything runs locally in your browser. When you close or refresh the page, your session is cleared.