Key takeaways
- Coding interviews test problem solving, code quality, communication and testing in about an hour.
- Prepare by pattern with curated problem lists, timed practice and mock interviews.
- Do not use ChatGPT in interviews unless explicitly allowed, and ask before looking up documentation.
- Cracking the Coding Interview is a solid foundation; Grokking is paid, with free alternatives.
- In research, interview coding means labelling transcript passages with themes.
Coding interviews test how you solve programming problems under time pressure while explaining your thinking, and they remain the main gate into software roles at most tech companies. Preparation is learnable, and structured practice beats random grinding. I have mentored more than 200 students since 2023, many preparing for placements, so this page covers how coding interviews work, preparing, acing and improving, live rounds, ChatGPT and Google rules, Cracking the Coding Interview, Grokking and interview coding in research.
How does a coding interview work?
You get one or two problems, usually on data structures and algorithms, and about 45 to 60 minutes to clarify requirements, propose an approach, write working code, test it and analyse complexity, all while explaining your reasoning aloud.
Also asked as: how does coding interview work · how to improve coding interview
The process often starts with an online assessment on platforms such as HackerRank, followed by one or more technical rounds, sometimes a system design round for experienced roles, and a behavioural or hiring manager round. Interviewers score problem solving, code quality, communication and testing, not only whether you finish. Indian campus placements frequently add aptitude tests and group discussions before technical rounds. Startups may replace algorithm puzzles with practical tasks, such as building a small feature or reviewing code. Ask the recruiter about the format, since knowing it shapes your preparation.
How do you prepare for a coding interview?
Learn core data structures and algorithms, then practise problems by pattern, such as two pointers, sliding window, binary search, graphs and dynamic programming, in one language you know well. Consistent daily practice over a few months beats last-minute cramming.
Also asked as: how to prepare coding interview
Use a curated list, such as the Blind 75 or NeetCode 150, rather than solving random problems, and revisit the ones you failed after a few days. Time yourself, and practise explaining solutions out loud, since silence is a common weakness. Do mock interviews with peers or on practice platforms to simulate pressure. Review company-specific formats and past questions, and prepare short stories about your projects for behavioural rounds. Keep a log of mistakes and patterns, turning each failed problem into a lesson you revisit.
How do you ace a coding interview?
Clarify the problem and constraints, talk through a brute-force approach, improve it, agree on the plan, then code cleanly, test with examples and edge cases, and state time and space complexity. Communication counts as much as the final answer.
Also asked as: how to ace coding interview
Interviewers want to see how you think, so narrate decisions and trade-offs instead of coding silently. If stuck, say what you are considering and use hints gracefully; recovering well is a positive signal. Write readable code with meaningful names and small helper functions. Test by walking through your code line by line before claiming it works. Manage time, and avoid spending twenty minutes on an approach you have not explained. End by mentioning possible optimisations. Calm, structured problem solving often beats a rushed perfect solution.
How do you improve at coding interviews?
Analyse why you fail: knowledge gaps, slow pattern recognition, bugs under pressure or weak communication each need different fixes. Then practise deliberately on that weakness instead of repeating problems you already find easy.
For knowledge gaps, study the topic from a book or course before attempting problems. For slow recognition, group problems by pattern and solve several in a row. For bugs, practise writing code without an IDE and dry-running it by hand. For communication, record yourself or do mock interviews and review the feedback. Revisit failed problems after a week to check you truly learned them. After real interviews, write down the questions and what went wrong while memory is fresh. Track progress weekly, such as problems solved without hints, so improvement stays visible.
How does a live coding interview work?
In a live coding interview, you solve a problem in real time while an interviewer watches, usually through a shared editor such as CoderPad or a video call with screen sharing, and you are expected to think aloud throughout.
Also asked as: how does live coding interview work
The interviewer may give hints, ask follow-up questions or change constraints to see how you adapt. Some companies let you run code; others use plain editors without autocomplete, so practise both. Before the interview, test your camera, microphone and internet, and keep a notebook for sketching. Ask whether you may use your preferred language. Live rounds differ from take-home assignments, where you build something on your own time. Treat the interviewer as a collaborator: ask clarifying questions, share your plan and confirm it before diving into code.
Can you use ChatGPT for a coding interview?
Not during the interview unless the company explicitly allows it. Most companies treat using ChatGPT or other AI assistants during a live or proctored interview as cheating, and detection or obviously scripted behaviour can end your candidacy.
Also asked as: can i use chatgpt for coding interview
Some companies now run AI-assisted interviews, where tools such as ChatGPT or coding assistants are permitted and interviewers evaluate how well you prompt, verify and integrate the output. Ask the recruiter about the policy for each round. For preparation, ChatGPT is valuable: ask it to explain concepts, review your solutions, generate similar problems or run mock interviews. Do not let it solve problems for you, since passing depends on your own skill. Honesty protects your reputation, which matters more than any single offer.
Can you use Google during a coding interview?
It depends on the company and round. Many live interviews allow looking up syntax or library documentation if you ask first, but searching for the full solution is not acceptable. Online assessments often prohibit switching tabs entirely.
Also asked as: can you google during coding interview
Always ask the interviewer whether you may check documentation, and say what you are looking up; transparency turns it into normal engineering behaviour. Proctored tests may monitor tab switches, webcam or screen, and violations can disqualify you. Take-home assignments usually allow full internet access, since they mirror real work, though copying code without attribution is still a problem. To reduce dependence, memorise common syntax for your language, such as sorting, maps, heaps and string handling, so lookups stay rare during live rounds.
Is Cracking the Coding Interview worth it?
Yes, for many candidates. Gayle Laakmann McDowell's Cracking the Coding Interview explains how interviews work and covers core topics with 189 problems and solutions, making it a strong foundation, though reading alone will not make you interview-ready.
The sixth edition dates from 2015, so pair it with online practice on platforms such as LeetCode and NeetCode for current problem styles. Its chapters on behavioural questions, offers and the interview process remain useful. A newer companion, Beyond Cracking the Coding Interview, published in 2025, focuses on patterns and practice strategy. If you prefer video and structured problem lists, free resources may be enough. Read the core chapters, attempt problems before reading solutions, and supplement with timed practice and mock interviews.
Is Grokking the Coding Interview free?
No. Grokking the Coding Interview is a paid course created by Design Gurus, organised around recurring problem patterns such as sliding window and two pointers. Some lessons may be available as free previews, and similar pattern courses exist on Educative.
It is popular because pattern-based learning helps you recognise how to approach unseen problems. Whether it is worth paying for depends on your learning style: free alternatives cover similar patterns, including NeetCode's roadmap and videos, the Tech Interview Handbook, and pattern lists shared by the community on LeetCode. If you buy it, combine it with practice on real problems and mock interviews. Avoid pirated copies, which may carry malware. Whichever resource you choose, consistent practice matters more than the specific course.
What is interview coding in research?
In qualitative research, coding means labelling segments of interview transcripts with short codes that capture themes, ideas or behaviours, so researchers can organise, compare and analyse what participants said. It has nothing to do with programming.
Researchers usually transcribe interviews, read them closely, then assign codes either from a predefined framework, called deductive coding, or from the data itself, called inductive coding. Codes are grouped into categories and themes, as in thematic analysis. Tools such as NVivo, ATLAS.ti and Taguette help manage codes, and teams compare coders to check consistency. AI tools can suggest initial codes, but researchers must review them, since meaning depends on context. The same skill appears in user research and product discovery, where interview insights shape what you build.
Sources
GenAI engineer and AI product builder with 2+ years shipping production-grade AI systems: RAG pipelines, fine-tuned LLMs, hybrid retrieval and multi-modal apps across vision, speech and OCR, architected end to end from ingestion to deployment. Leads engineering for SCULT INDIA's 14-member team, founded the 500+ member TechVerse Enclave community and has mentored 200+ students. Three hackathon first prizes: Changethon 2025 (IIT Roorkee), Product Genesis at Vividhotsava 2025 (CSJMU) and BYTEBATTLE (MeetKats).
Open to GenAI roles, hackathon judging, mentorship sessions and guest talks at colleges. For campus sessions the inviting institution covers the visit end to end: travel (a First AC train ticket for journeys up to five hours, a flight for anything longer), accommodation, meals, and pickup and drop; the honorarium and workshop fees are negotiable on WhatsApp or on the call, and requests are welcome from institutions that can cover the visit this way. Email pranjulrathour41@gmail.com.
