500+ Challenges
A vast arsenal of JavaScript questions covering every corner of the language — from basics to black magic.
Question BankThe ultimate JavaScript quiz game for web developers. Master closures, promises, prototypes & more. Claim your throne.
JS King throws real JavaScript gotchas at you — the kind that trip up developers at every level. No multiple choice luck here. You either know your JS or you don't.
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Every feature designed to make you a better JavaScript engineer — or expose the gaps you didn't know you had.
A vast arsenal of JavaScript questions covering every corner of the language — from basics to black magic.
Question BankNo theoretical questions. Every challenge shows you actual JavaScript execution results — exactly what a browser or Node.js would output.
AuthenticStart as a JavaScript Peasant. Progress through Knight, Wizard, and Legend tiers as your skills sharpen.
ProgressionA fresh set of challenges delivered every day. Build your streak, maintain your edge, and never stop learning.
DailyCompete with developers worldwide. See where you rank among JavaScript champions and fight for the top spot.
CompeteEvery wrong answer comes with a detailed explanation — turning each mistake into a powerful learning moment.
Educational"The only way to truly know JavaScript is to be tested by it."
Download JS King free on Android and begin your journey from JavaScript apprentice to undisputed king. Every question is a step closer to the throne.
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