You know the stakes. You’re preparing for a life-changing coding interview at Google, Amazon, Meta, Netflix, or that fast-growing startup you love. But every time you open LeetCode or crack open a system design PDF, the anxiety sets in.
What should I focus on first? How much time do I need? Am I doing this the right way?
Here’s the good news:
This is your step-by-step guide to studying for a coding interview, built from real hiring loops, hundreds of candidate journeys, and behind-the-scenes experience.
You’ll learn:
- What to study and in what order
- How long to prepare and what schedule to follow
- Where most candidates fail (and how to avoid it)
- The best platforms and resources to use
- What to do the week before your interview
First, understand the game you’re playing
If you’re wondering how to study for coding interviews, the first step is knowing what the interview actually tests.
It’s not just about solving problems.
It’s about:
- Problem solving under time pressure
- Communicating your thought process
- Writing clean, bug-free code
- Navigating edge cases
- Handling follow-up questions on the fly
In short, it’s not just “Can you solve it?” It’s “Can you solve it well while speaking clearly and thinking like an engineer?”
Phase 1: Set your timeline
Before you jump into blind practice, set a clear roadmap for your coding interview.
How long should you prepare?
- Beginner (little to no DSA): 3–4 months, 10–15 hrs/week
- Intermediate (some prep before): 1–2 months, 8–10 hrs/week
- Experienced engineer: 3–5 weeks of focused review
The timeline depends on your current skills and how recently you practiced.
If you’re starting from scratch, give yourself space. It’s better to overprepare than panic the week before.
Phase 2: Master the fundamentals (weeks 1–2)
Your foundation matters. Even senior candidates get tripped up by a poor understanding of basic data structures.
Start with these core topics:
- Arrays and Strings
- Hash Tables
- Stacks and Queues
- Linked Lists
- Two Pointers
- Sliding Window
Use these resources:
- Cracking the Coding Interview (CTCI): best for walkthroughs
- LeetCode: easy and medium problems by topic
- Educative’s Grokking the Coding Interview: pattern-first approach
Your goal:
Build speed and confidence in these areas. Aim to solve Easy/Medium problems in 15–20 minutes with clear explanations.
Phase 3: Dive into algorithms (weeks 3–6)
Once your fundamentals are solid, level up with deeper problem types.
Key algorithms to study:
- Recursion and Backtracking
- Sorting and Searching
- Binary Search
- Dynamic Programming
- Trees and Graphs
- Heaps and Tries
These are high-leverage topics, so they show up often and test real algorithmic thinking.
How to approach:
- Group problems by pattern (e.g., all BFS/DFS variants together)
- Practice whiteboarding or verbal walkthroughs
- Study brute-force first, then optimize
- Use pseudocode before real code if you get stuck
Phase 4: Simulate the real thing (weeks 7–9)
Once you’ve logged 100–150 problems, it’s time to move past brute-force drilling.
This is where most candidates fall short.
You need to simulate real interviews. That means:
- Solving problems in 30–45 minute sessions
- Talking through your process out loud
- Writing code on a shared doc or whiteboard
- Handling curveball follow-up questions
Mock interview formats to try:
- MockInterviews.dev
- Interviewing.io (with engineers from FAANG)
- Friends or colleagues on Zoom (yes, it works)
The goal here isn’t perfection. It’s to practice pressure and to build comfort with awkward silences, clarifications, and debugging.
Phase 5: Master behavioral and system design (weeks 10–11)
Even for junior roles, behavioral and system design rounds can make or break your offer.
A. Behavioral Interviews
Common formats:
- “Tell me about a time you…” (conflict, challenge, leadership, failure)
- “Why this company?”
- “What would your teammates say about you?”
Use the STAR method:
- Situation: Set context
- Task: Define the challenge
- Action: What you did
- Result: What changed
Have 4–5 stories ready that show:
- Ownership
- Collaboration
- Resilience
- Creativity
Tip: Practice recording your answers and playing them back. It’s uncomfortable, but powerful.
B. System Design (even for L3–L4 SWE)
You may get a light design round or “design a simple app” prompt.
Focus on:
- Scalability basics (caching, load balancing, queues)
- Common architectures (messaging, real-time updates)
- Trade-off thinking (latency vs. consistency)
Study resources:
- System Design Guide (Educative)
- Alex Xu’s System Design Interview book
- YouTube: Gaurav Sen, Tech Dummies, Exponent
Phase 6: The final sprint (week before interview)
The last 7 days are about confidence and clarity, not cramming.
What to do:
- Review your 10–15 favorite solved problems
- Rehearse behavioral stories
- Do 2–3 mock interviews
- Revisit frameworks: Binary Search patterns, Graph traversal, etc.
- Read Glassdoor and Blind posts about your target company’s process
What not to do:
- Don’t try to learn an entirely new algorithm
- Don’t stay up late grinding LeetCode
- Don’t copy/paste answers from solution guides
Trust your prep. Sleep well. Eat real food. You got this.
Common mistakes to avoid
If you’re learning how to study for coding interviews, avoid these traps:
❌ 1. Grinding blindly
Solving 300 random problems without understanding patterns wastes time. Focus on depth, not just volume.
❌ 2. Ignoring mock interviews
The #1 difference between pass and fail isn’t knowledge. It’s interview performance.
❌ 3. Skipping behavioral prep
Some candidates lose the offer because of a single awkward or arrogant answer. Practice like it matters (because it does).
❌ 4. Comparing to others
Your journey is your own. Don’t panic if someone else finished the Blind 75 in a week. Stay consistent.
What hiring managers are looking for
Beyond solving the problem, here’s what top interviewers actually evaluate:
| Trait | What It Looks Like |
|---|---|
| Communication | Thinking out loud, explaining trade-offs, asking clarifying questions |
| Clean code | Naming, structure, and no copy-paste solutions |
| Problem-solving mindset | Step-by-step exploration, testing edge cases |
| Coachability | Accepting hints, revising the approach mid-way |
| Calm under pressure | Managing time and complexity without spiraling |
FAQs: How to study for a coding interview
How many problems should I solve?
Aim for 100–150 solid problems across patterns. It’s not about how many, but what you learn from each one.
Is LeetCode enough?
LeetCode is great, but not sufficient alone. Combine it with:
- Mock interviews
- System design prep
- Behavioral story crafting
How do I know when I’m ready?
When you can:
- Solve unseen mediums in 30–35 mins
- Talk through solutions out loud
- Tackle behavioral questions without stumbling
Bonus: Sample 6-week study plan
| Week | Focus | Goals |
|---|---|---|
| 1 | Arrays, Strings, Hash Tables | 25 problems + learn common edge cases |
| 2 | Linked Lists, Two Pointers, Stacks/Queues | 20 problems + practice out-loud explanations |
| 3 | Trees, Graphs, Recursion | 25 problems + dry-run with sample questions |
| 4 | Binary Search, Heaps, Sliding Window | 20 problems + review past mistakes |
| 5 | Mock interviews + behavioral questions | 3 mocks + write 5 STAR stories |
| 6 | Review, light system design, final prep | Re-solve hard problems + sleep + simulate final loop |
Final thoughts
If you’re serious about landing the job, studying for a coding interview is about learning how to perform under pressure.
So don’t just memorize patterns. Don’t just speed-run LeetCode. Instead:
- Learn the fundamentals
- Practice consistently
- Simulate real interviews
- Refine your stories
- Stay calm and focused
Remember: your goal isn’t to ace one round. Your goal is to become the kind of engineer companies want to work with, someone who is collaborative, clear, and capable under stress.
And with the right prep plan? That can absolutely be you.