JS Code Lab — 100 Interactive Challenges

Description

Stop reading about JavaScript. Start writing it.

JS Code Lab is a single interactive HTML file with 100 JavaScript coding challenges — organized by topic, graded instantly, no account needed, no internet required after download.

Write your solution directly in the built-in code editor. Hit Run. Get instant feedback:
✓ Correct Answer — all test cases passed
✗ Try Again — shows exactly what went wrong, with the failing input and expected output

Every challenge runs against real hidden test cases — not just one example, so you actually have to solve it properly.

What’s inside:

• 100 challenges across 10 topics
• Strings (12) · Arrays (14) · Numbers & Math (10) · Objects (11)
• Loops & Algorithms (12) · Higher-Order Functions (8) · Recursion (8)
• Sorting & Searching (7) · ES6+ Features (10) · Async & Promises (8)
• Built-in code editor with syntax highlighting
• Instant pass/fail grading with debug output
• Reference solution + explanation for every challenge
• Search bar to jump to any topic instantly
• Works offline — open in any browser, no login, no subscription

Who is this for?

• JavaScript beginners who want to go beyond tutorials
• Developers preparing for technical interviews
• Students who learn best by doing, not reading

How to use:

Download → Unzip → Open js-code-lab.html in Chrome or Firefox → Start coding.

That’s it. No setup. No account. No expiry.

One file. 100 challenges. Instant feedback.