The Blind 75 is the closest thing to a consensus study list that coding interview prep has. Seventy-five problems, chosen to cover the patterns that show up most in FAANG and top-tech interviews. If you know how to use the right resources alongside it, the list does its job fast. This guide covers what the Blind 75 actually is, how its problems break down by pattern, and which platforms help you get the most out of it.
Table of Contents
- What Is the Blind 75 and Why It Still Works
- The Blind 75 Problems Grouped by Pattern
- LeetCode: The Official Platform for Blind 75 Practice
- NeetCode: Video Explanations and Structured Roadmap
- Phantom Code AI: Real-Time Guidance During Blind 75 Practice
- How to Build a Study Schedule Around the Blind 75
- FAQ
- Conclusion
What Is the Blind 75 and Why It Still Works
The list was posted on Blind, a forum where engineers talk candidly about interviews and compensation. The problem it was solving was simple: there were thousands of LeetCode problems and no clear signal about which ones mattered most.
The answer was a curated set of 75 problems spanning arrays, trees, graphs, dynamic programming, binary search, and linked lists. The goal was not to cover everything. It was to cover the 20% of problems that appear in 80% of real interviews. That Pareto framing is exactly why the list still works in 2026.
Before the Blind 75 existed, a lot of engineers fell into random grinding. They'd solve hundreds of problems without building pattern recognition, then freeze when they hit something slightly unfamiliar. The list fixed that by forcing depth over volume. Seventy-five problems is an achievable target. More important, the problems repeat core techniques enough that you start to internalize them rather than memorize solutions.
One reason it has lasted is that it respects your time. Most engineers preparing for interviews are also working or in school. A fixed, high-signal list keeps motivation up and removes decision fatigue. You don't spend 20 minutes choosing what to practice. You open the list and start.
The list is not perfect for every situation. Senior engineers often need to layer in system design and more advanced dynamic programming after finishing the 75. And if you have several months before your first application, a broader curriculum like NeetCode 150 or an extended study plan might give you more ramp-up. But as a foundation, the Blind 75 has held up because the patterns it covers are not fads. Arrays, trees, BFS/DFS, and DP appear in interviews at every tier of the industry.
LeetCode has become a central resource for software engineers preparing for industry technical interviews, which tracks with why community-curated lists like the Blind 75 gained so much traction on top of it.
The Blind 75 Problems Grouped by Pattern
The most common version of the list organizes problems by data structure. That's useful for tracking what you've covered. But a pattern-based lens is more useful for building interview instincts, because interviewers care about your approach, not which bucket you filed the problem into.
Here's how the 75 problems break down by data structure category, with difficulty counts drawn from the standard distribution:
| Category | Easy | Medium | Hard | Total | Key Patterns Inside |
|---|---|---|---|---|---|
| Arrays | 3 | 7 | 0 | 10 | Sliding window, two pointers, prefix sum |
| Strings | 3 | 6 | 1 | 10 | Hashing, sliding window, two pointers |
| Trees | 4 | 7 | 3 | 14 | DFS, BFS, recursion, level-order traversal |
| Dynamic Programming | 1 | 10 | 0 | 11 | Memoization, tabulation, 1D and 2D DP |
| Graphs | 0 | 7 | 1 | 8 | BFS, DFS, topological sort, union find |
| Linked Lists | 3 | 2 | 0 | 5 | Fast/slow pointers, reversal, merging |
| Binary | 4 | 1 | 0 | 5 | Bit manipulation |
| Intervals | 1 | 4 | 0 | 5 | Greedy, sorting, sweep line |
| Matrix | 0 | 4 | 0 | 4 | DFS, BFS, in-place marking |
| Heap | 1 | 0 | 2 | 3 | Priority queue, top-K problems |
Trees and dynamic programming together account for 25 of the 75 problems. That weighting is intentional. Tree traversal comes up constantly in real interviews. DP is the category most candidates avoid, and the list forces you to face it directly.
Pattern recognition is what actually transfers to new problems. When you see a problem asking for the longest substring without repeating characters, the insight is not the specific problem. It's that the sliding window pattern works here, the same way it works for dozens of other windowed array or string problems. Once you've labeled that pattern ten times, you stop needing to re-derive it.
For engineers who want to build that habit systematically, the top LeetCode patterns every engineer should know is a good companion resource that maps the core strategies behind these categories.
A few categories deserve extra attention because candidates consistently underweight them. Graphs are harder to practice because the setup takes longer than a simple array problem. But graph problems cover BFS, DFS, topological sort, and union find , all of which appear in real onsite loops. The heap section is small (just 3 problems) but the hard problems in it show up disproportionately at senior levels.
Dynamic programming deserves its own note. With 11 problems, it's the densest category after trees. The standard trap is trying to memorize DP solutions. What actually works is understanding the subproblem structure first. Ask: what's the smallest version of this problem I can solve? Then build up from there. That approach works on Climbing Stairs, Coin Change, and Longest Increasing Subsequence , and it transfers to new DP problems you've never seen.
LeetCode: The Official Platform for Blind 75 Practice
LeetCode is where the Blind 75 lives. Every problem on the list has a corresponding LeetCode page, which means you get automated test cases, a code editor, and a discussion forum for each one. The free tier covers most of the Blind 75, though some editorial solutions and company-tagged problems sit behind a premium paywall.
LeetCode also has its own official study plan — a structured path with built-in progress tracking, daily streaks, and a badge on completion. The two lists are not the same: the official plan is organized as a progressive curriculum, starting easier and moving toward medium-hard, while the community Blind 75 is a fixed set organized by topic bucket without a built-in difficulty ramp.
Which one you use depends on where you are in prep. If you have a solid algorithms background and under four weeks before interviews, the community Blind 75 is the faster revision path. If you're newer to data structures and have two to three months, a progressive curriculum works well as a foundation before you switch to broader problem sets.
LeetCode does not have AI assistance built in for problem-solving guidance. It provides mock interviews and online assessments, which is useful for simulating the test environment. But the lack of real-time hints means you're largely on your own when you get stuck. That's fine for deliberate practice, but it can slow you down if you're spending 45 minutes stalled on a graph problem you don't yet understand.
The platform's discussion tabs can partially fill that gap. For almost every Blind 75 problem, the community has posted multiple solution approaches in different languages. Reading through those after you've attempted a problem is one of the best ways to see alternative strategies you wouldn't have found on your own.
NeetCode: Video Explanations and Structured Roadmap
NeetCode is a free platform built specifically around structured algorithm prep. It has full coverage of the Blind 75, and its biggest differentiator is video: the founder recorded clear, concise YouTube explanations for every problem on the list. Those videos walk through the pattern, the approach, and the complexity analysis , not just the code.
The NeetCode roadmap organizes problems into the same category groups that appear in the Blind 75: arrays and hashing, two pointers, sliding window, stack, binary search, linked list, trees, heap and priority queue, backtracking, tries, graphs, advanced graphs, 1D dynamic programming, 2D dynamic programming, greedy, intervals, math and geometry, and bit manipulation. That's 18 categories. The visual roadmap makes it easy to see what you've covered and what's left.
NeetCode also includes NeetBot, an AI assistant with hints and debug support. This is useful during active practice when you've been stuck for more than 15 minutes and need a nudge toward the right pattern without seeing the full solution. The free tier gives access to the full roadmap and all the YouTube video explanations, which makes it genuinely accessible regardless of budget.
The main limitation is that NeetCode does not list mock interview support as a feature. It's a practice and learning platform, not a simulation environment. So if you're using NeetCode to prepare, you'll need to pair it with something else for timed, interview-format practice. That pairing matters more than most candidates realize: knowing how to solve a problem and performing under a 45-minute clock are different skills.
For engineers who work best by watching a concept before coding it, NeetCode fills a gap that LeetCode's text-based editorials leave open. The videos are short and direct. Most run 10 to 20 minutes and cover the intuition before the code, which matches how you actually want to think about problems during a real interview.
Phantom Code AI: Real-Time Guidance During Blind 75 Practice
LeetCode gives you test cases and a code editor. NeetCode gives you video explanations and structured roadmaps. What neither does is sit with you during a live or mock interview session and help you think through a problem in real time, the way a strong prep partner would.
That's what Phantom Code AI does. It's a desktop assistant that listens to your interview session, transcribes the problem as it's read aloud, recognizes the problem type, and surfaces real-time guidance on approach, pattern, and complexity. It works during both mock sessions you run yourself and live technical interviews.
The usable difference matters during Blind 75 practice. When you pull up a graph problem and stall after five minutes, you don't want to close your editor, open a browser tab, and watch a video. You want a hint that keeps you in the problem. Phantom Code AI stays in the background, gives you a nudge toward the right pattern , BFS or DFS, say, and what constraints suggest one over the other , and lets you keep working.
Among the platforms covered in this guide, Phantom Code AI is the only one that combines AI assistance with mock interview support in a single tool. LeetCode has mock interviews but no AI guidance during the session. NeetCode has AI hints via NeetBot but no mock interview environment. If you want both in one place, Phantom Code AI is the option the research supports.
The tool also does something worth noting for engineers who struggle with the communication side of coding interviews: because it transcribes the problem and tracks your approach, it builds a record of how you're thinking through problems over time. That's useful for identifying weak spots , not just in your code, but in how you narrate your reasoning, which FAANG interviewers weigh heavily.
For working engineers with limited prep time, the combination of AI hints and built-in mock interview support means you can do a full practice loop (problem, hints when stuck, timed session, debrief) without switching between four different tools.
How to Build a Study Schedule Around the Blind 75
The 75 problems are manageable if you treat them as a structured schedule rather than a pile to chip through randomly. An eight-week plan is realistic for most working engineers, assuming five to ten hours per week. Here's how to sequence it.
Weeks 1 to 2: Arrays, Strings, and Linked Lists
Start with the easy and medium array and string problems. These reinforce the fundamentals , two pointers, sliding window, hash maps , and build confidence without throwing you into the deep end. Add linked list problems here too. The reversal and cycle detection patterns are fast to learn and appear frequently enough that you want them locked in early.
Set a 20-minute timer for each problem. If you're stuck after 20 minutes, look at the pattern name (not the solution). Then re-solve from scratch. That constraint keeps you from stalling for an hour on a single problem and losing a full practice session.
Weeks 3 to 4: Trees and Binary Search
Trees are the single largest category in the Blind 75 with 14 problems. Spend two full weeks here. Work through DFS and BFS first, then recursive tree construction and level-order traversal. Binary search fits naturally alongside trees because both rely on divide-and-conquer thinking.
By the end of week 4, you should be able to write a recursive tree traversal from memory and recognize when a problem calls for BFS versus DFS based on the constraints. If that's not clicking yet, redo the problems you struggled with before moving on.
Weeks 5 to 6: Graphs, Intervals, Matrix, and Heap
This block covers the categories that most candidates deprioritize. Graphs take longer to set up, but the patterns repeat: BFS for shortest path, DFS for connected components, topological sort for dependency ordering. Intervals need a sorting step first, then a greedy sweep. Heap problems almost always ask for top-K elements, which maps cleanly to a min-heap or max-heap.
Run at least two timed mock sessions this block. Pick a problem from the section you're on, set a 45-minute clock, and narrate your approach out loud as you code. That's the closest approximation to a real interview you can do alone.
Weeks 7 to 8: Dynamic Programming and Final Review
Save DP for last. It's the hardest category and benefits from having the other patterns already in place. Work through the 1D problems first (Climbing Stairs, House Robber, Coin Change), then move to 2D (Longest Common Subsequence, Edit Distance). Focus on the subproblem definition and the recurrence relation for each one, not the code shape.
The final week should include spaced repetition on every problem you got wrong earlier. Pull them up without hints and solve them again. If you can solve the Blind 75 problems cold in under 30 minutes each, you're ready for most mid-level coding loops.
Engineers balancing this prep alongside a job will find the week-by-week breakdown in the complete LeetCode study plan for busy professionals useful for managing the time commitment realistically.
Throughout all eight weeks, track every problem in a simple spreadsheet: problem name, category, time to solve, whether it was a first attempt, and what pattern it used. Reviewing that log before each session shows you exactly where your gaps are, which is more useful than reviewing problems at random.
Building strong interview skills shares something with building expertise in any high-pressure domain: systematic preparation beats last-minute cramming every time. The same principle applies across fields that require performing under pressure with clear frameworks, whether that's technical interviews or negotiation training for high-stakes professional roles.
FAQ
What is the LeetCode Blind 75?
The Blind 75 is a curated list of 75 coding interview problems originally published by Yangshun Tay, a former Meta engineer, around 2020. The list covers core data structures and algorithm patterns , arrays, trees, graphs, dynamic programming, and more , that appear most frequently in technical interviews at major tech companies. It's designed to give engineers a focused, high-yield prep path rather than grinding hundreds of random problems.
How long does it take to finish the Blind 75?
Most working engineers finish the Blind 75 in six to twelve weeks, spending five to ten hours per week. A tighter timeline (four to six weeks) is realistic if you already have a solid algorithms foundation and can dedicate more time daily. Plan around forty to fifty minutes per problem across two sessions , one to attempt it and one to re-solve it the next day from memory.
Is NeetCode free for Blind 75 prep?
Yes. NeetCode's free tier includes the full Blind 75 roadmap and video explanations for every problem on its YouTube channel. The NeetBot AI assistant is also available on the free tier for hints and debug support. Some advanced NeetCode courses and features require a paid subscription, but the core Blind 75 resources are fully accessible without paying.
Do I need LeetCode Premium to practice the Blind 75?
No. The vast majority of Blind 75 problems are on LeetCode's free tier. Some editorial solutions and company-specific problem tags sit behind a premium paywall, but the problems themselves are free. Many candidates complete the full Blind 75 without a premium account by using community discussion threads and NeetCode's video explanations for solution guidance.
What's the difference between Blind 75 and an official platform study plan?
Blind 75 is a community-curated list made by a Meta engineer, focused on the highest-frequency interview patterns. Official platform study plans tend to be structured as progressive curricula for beginners who want guided pacing over one to three months. Blind 75 is better as a fast, focused revision tool for candidates close to interview dates, while a structured platform plan suits those who want more hand-holding through core topics.
Can I use an AI tool during Blind 75 practice?
Yes, and it can genuinely speed up learning if used correctly. Tools like Phantom Code AI provide real-time hints during practice sessions without just handing you the solution. The key is to attempt each problem yourself first, then use AI guidance when you've been stuck for more than fifteen to twenty minutes. That approach keeps you building pattern recognition instead of just reading answers.
Conclusion
The Blind 75 works because it's focused, not because it's exhaustive. Pair it with LeetCode for problem access, NeetCode for video-driven pattern learning, and Phantom Code AI when you want real-time guidance during timed mock sessions. If you're mapping out your prep week by week, start with the arrays and trees sections , they give you the fastest return on time spent , and save dynamic programming for when the other patterns are already solid.