Console & Developer Tools
A free lesson from Swipe Coding · JavaScript, level 2 · updated October 2026
By the Swipe team, founded by Colin · how we make lessons
Every browser includes a set of built-in Developer Tools for inspecting, testing, and debugging what's happening on a web page. You can open them by pressing F12, or by right-clicking anywhere on a page and choosing "Inspect."
One of the most useful panels inside Developer Tools is the Console tab. It shows messages that JavaScript running on the page has logged, along with any errors or warnings — and it also works as a live JavaScript prompt where you can type code and run it immediately.
console.log('Debugging message here');console.log() can print numbers, text, variables, or several values at once separated by commas. Sprinkling console.log() calls through your code is one of the simplest and most common ways to 'peek inside' a program while it runs and see exactly what's happening.
let score = 10;
console.log('Current score:', score);The browser panel used to inspect, test, and debug code on a web page is called ____.
Which function is most commonly used to print messages to the browser console for debugging?
You can type and run JavaScript directly inside the Console tab of Developer Tools.
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