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AI JavaScript interviewer
Closures, the event loop, promises and prototypes — practice explaining JavaScript precisely, with follow-ups that find the gaps.
Free 10-minute interview with a full report. Paid plans run full-length sessions.
JavaScript interview questions you might get
A sample of the starting questions. The live interview follows up on your answer, so no two sessions go the same way.
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Implement debounce, then explain how it differs from throttle.
What it tests: Closures in practice.
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What is the output order of a mix of setTimeout, Promise.then and console.log — and why?
What it tests: Microtasks versus macrotasks.
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Explain how `this` is determined in four different call styles.
What it tests: Binding rules.
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Implement Promise.all from scratch.
What it tests: Async fundamentals.
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How can a closure cause a memory leak in a long-running app?
What it tests: Runtime awareness.
How a session works
About 20–30 minutes from setup to report. End any time and you still get feedback on what was covered.
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Set your target
Pick a role, level and stack. Add a job description or your resume if you want questions about your real projects.
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Answer live
Speak or type. The interviewer follows up on thin answers, raises the difficulty when you're doing well and switches to code when it fits.
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Read the notes
A report scores every competency, quotes the answers that cost you, and gives you a prep plan for the next session.
A report that quotes you, not a pat on the back
Every score links back to something you actually said.
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Competency scores
Weighted to the role you picked, so a system design gap counts more for a senior backend role than for a frontend junior.
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STAR check on every story
See which part of each behavioral answer was missing — usually the Result.
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How you sounded
Filler words, hedging, "I" versus "we", and whether you cited real numbers — measured from your words, and compared between the first and second half of the interview.
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A prep plan
The two or three things to practice next, and a skill graph that tracks them across sessions.
Competencies — sample report
STAR — "Tell me about a missed deadline"
How you sounded
Questions
Does it include TypeScript?
Add TypeScript to your stack in the setup and questions will include typing.
Frontend or Node.js?
Both are covered. Add React for frontend focus or Node.js for backend focus.
How are code answers judged?
Your code snapshot is reviewed for correctness and clarity, together with how you explained it.
Is it free to try?
Yes. Each month you get a free interview of up to 10 minutes with its scored report. Paid plans add full-length interviews, every track and the full 360 report.