Top 100 Coding Interview Questions by Company (2026)
This is the definitive list of the 100 most frequently asked coding interview questions at Google, Amazon, Meta, Microsoft, and Apple. Compiled from thousands of interview reports, this list covers every major topic and pattern you will encounter. Each question is tagged with difficulty, topic, and the companies that ask it most frequently. All 100 can be practiced for free on Guru Sishya with lessons, quizzes, and a built-in code playground.
How This List Was Compiled
This list is compiled from multiple data sources: interview experience reports on platforms like Glassdoor and Blind, publicly available interview question databases, and direct feedback from engineers who have interviewed at these companies in 2025-2026. Questions are ranked by frequency — how often they appear in real interview loops.
Unlike random LeetCode grinding, this list is structured to maximize your interview readiness. The questions are organized by company first, then by pattern. If you are preparing for a specific company, focus on their section first, then work through the cross-company essentials. If you are doing general preparation, start from question 1 and work through all 100 in order.
Each question on Guru Sishya comes with a complete lesson explaining the underlying concept, multiple solution approaches (brute force through optimal), code in Java and Python, time/space complexity analysis, and related practice problems.
Jump to Company
Google Top Interview Questions
Most frequently asked coding questions at Google in 2025-2026.
Amazon Top Interview Questions
Most frequently asked coding questions at Amazon in 2025-2026.
Meta Top Interview Questions
Most frequently asked coding questions at Meta in 2025-2026.
Microsoft Top Interview Questions
Most frequently asked coding questions at Microsoft in 2025-2026.
Apple Top Interview Questions
Most frequently asked coding questions at Apple in 2025-2026.
Complete List: All 100 Questions
| # | Question | Difficulty |
|---|---|---|
| 1 | Two Sum | Easy |
| 2 | Longest Substring Without Repeating Characters | Medium |
| 3 | Median of Two Sorted Arrays | Hard |
| 4 | Regular Expression Matching | Hard |
| 5 | Merge K Sorted Lists | Hard |
| 6 | Trapping Rain Water | Hard |
| 7 | Word Ladder | Hard |
| 8 | LRU Cache | Medium |
| 9 | Course Schedule | Medium |
| 10 | Serialize and Deserialize Binary Tree | Hard |
| 11 | Best Time to Buy and Sell Stock | Easy |
| 12 | Number of Islands | Medium |
| 13 | Merge Intervals | Medium |
| 14 | Word Break | Medium |
| 15 | Copy List with Random Pointer | Medium |
| 16 | Reorder Data in Log Files | Medium |
| 17 | Partition Labels | Medium |
| 18 | K Closest Points to Origin | Medium |
| 19 | Rotting Oranges | Medium |
| 20 | Min Cost to Connect All Points | Medium |
| 21 | Valid Palindrome | Easy |
| 22 | Add Binary | Easy |
| 23 | Move Zeroes | Easy |
| 24 | Subarray Sum Equals K | Medium |
| 25 | Binary Tree Right Side View | Medium |
| 26 | Vertical Order Traversal | Hard |
| 27 | Lowest Common Ancestor of Binary Tree | Medium |
| 28 | Random Pick with Weight | Medium |
| 29 | Minimum Remove to Make Valid Parentheses | Medium |
| 30 | Buildings With an Ocean View | Medium |
| 31 | Reverse Linked List | Easy |
| 32 | Valid Parentheses | Easy |
| 33 | Spiral Matrix | Medium |
| 34 | Group Anagrams | Medium |
| 35 | Longest Palindromic Substring | Medium |
| 36 | String to Integer (atoi) | Medium |
| 37 | Maximal Rectangle | Hard |
| 38 | Find All Anagrams in a String | Medium |
| 39 | Set Matrix Zeroes | Medium |
| 40 | Excel Sheet Column Title | Easy |
| 41 | Contains Duplicate | Easy |
| 42 | Roman to Integer | Easy |
| 43 | 3Sum | Medium |
| 44 | Letter Combinations of Phone Number | Medium |
| 45 | Decode Ways | Medium |
| 46 | Product of Array Except Self | Medium |
| 47 | Maximum Subarray | Medium |
| 48 | Container With Most Water | Medium |
| 49 | Coin Change | Medium |
| 50 | Climbing Stairs | Easy |
| 51 | House Robber | Medium |
| 52 | Longest Common Subsequence | Medium |
| 53 | Edit Distance | Hard |
| 54 | Unique Paths | Medium |
| 55 | Jump Game | Medium |
| 56 | Longest Increasing Subsequence | Medium |
| 57 | Validate Binary Search Tree | Medium |
| 58 | Invert Binary Tree | Easy |
| 59 | Maximum Depth of Binary Tree | Easy |
| 60 | Level Order Traversal | Medium |
| 61 | Construct Binary Tree from Preorder and Inorder | Medium |
| 62 | Kth Smallest Element in BST | Medium |
| 63 | Linked List Cycle | Easy |
| 64 | Merge Two Sorted Lists | Easy |
| 65 | Remove Nth Node From End | Medium |
| 66 | Reorder List | Medium |
| 67 | Clone Graph | Medium |
| 68 | Pacific Atlantic Water Flow | Medium |
| 69 | Graph Valid Tree | Medium |
| 70 | Alien Dictionary | Hard |
| 71 | Top K Frequent Elements | Medium |
| 72 | Find Median from Data Stream | Hard |
| 73 | Search in Rotated Sorted Array | Medium |
| 74 | Find Minimum in Rotated Sorted Array | Medium |
| 75 | Implement Trie | Medium |
| 76 | Design Add and Search Words | Medium |
| 77 | Word Search | Medium |
| 78 | Combination Sum | Medium |
| 79 | Permutations | Medium |
| 80 | Subsets | Medium |
| 81 | Min Stack | Medium |
| 82 | Daily Temperatures | Medium |
| 83 | Car Fleet | Medium |
| 84 | Largest Rectangle in Histogram | Hard |
| 85 | Minimum Window Substring | Hard |
| 86 | Sliding Window Maximum | Hard |
| 87 | Longest Repeating Character Replacement | Medium |
| 88 | Palindrome Partitioning | Medium |
| 89 | N-Queens | Hard |
| 90 | Rotate Image | Medium |
| 91 | Surrounded Regions | Medium |
| 92 | Word Search II | Hard |
| 93 | Meeting Rooms II | Medium |
| 94 | Insert Interval | Medium |
| 95 | Non-overlapping Intervals | Medium |
| 96 | Longest Consecutive Sequence | Medium |
| 97 | Task Scheduler | Medium |
| 98 | Design Twitter | Medium |
| 99 | Maximum Product Subarray | Medium |
| 100 | Burst Balloons | Hard |
How to Use This List: 6-Week Study Plan
Week 1-2: Focus on Easy problems across all topics. Build pattern recognition. Aim for 3-4 problems per day. Do not look at solutions for at least 20 minutes per problem.
Week 3-4: Move to Medium problems. This is where most interview questions fall. Learn to identify patterns quickly: Is this a sliding window problem? A BFS/DFS? Dynamic programming? Aim for 2-3 problems per day with full complexity analysis.
Week 5: Tackle Hard problems and revisit Medium problems you struggled with. Start timed practice: 25 minutes for Medium, 40 minutes for Hard.
Week 6: Mock interviews. Do 2-3 full mock interview sessions with Guru Sishya's interview mode. Review all your weak areas one final time.
Practice All 100 Questions for Free
Every question comes with lessons, code in Java and Python, quizzes, and a built-in code playground. No signup, no payment, no ads.