Etsy Coding Interview Questions
28 Etsy coding interview problems with full optimal solutions — 19 easy, 7 medium, 2 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an Etsy interviewer values, and a FAQ section.
Showing 28 problems of 28
- #17easyfoundational
17. Ransom Note
Determine whether a string can be built from the letters of another — Etsy uses this pattern to check if a listing title can be composed from a seller's available tag inventory.
- #18easyfoundational
18. First Bad Version
Binary-search for the first failing deployment version — Etsy's CI pipeline problem that every engineer needs to solve before touching their release train.
- #19easyfoundational
19. Top K Frequent Elements
Return the k most frequent elements — the direct model behind Etsy's 'best-selling items in a category' ranking that drives the search results page.
- #20mediumfoundational
20. Implement Trie (Prefix Tree)
Build insert/search/startsWith on a trie — the exact data structure powering Etsy's search autocomplete as buyers type listing keywords.
- #21mediumfoundational
21. Product of Array Except Self
Compute prefix-product arrays without division — a pattern Etsy uses internally for price-range normalization across listing categories where any element could be zero.
- #22mediumfoundational
22. Number of Islands
Count connected components in a grid — Etsy uses this BFS/DFS graph pattern to cluster seller locations into regional fulfillment zones.
- #23mediumfoundational
23. Merge Intervals
Collapse overlapping time ranges into non-overlapping intervals — the core algorithm Etsy uses to merge seller promotional sale windows before applying discounts.
- #24mediumfoundational
24. LRU Cache
Build a Least Recently Used cache with O(1) get and put — the exact eviction policy Etsy uses for its listing-detail cache to keep hot products in memory without unbounded growth.
- #25mediumfoundational
25. Coin Change
Find the fewest coins to make an amount — Etsy's checkout team uses the same DP pattern to compute the minimum number of coupon denominations needed to cover a buyer's order total.
- #26mediumfoundational
26. Group Anagrams
Cluster strings that are anagrams of each other — Etsy uses this hash-key normalization pattern to deduplicate misspelled listing tags ('handmade', 'hnadmade') before indexing.
- #27hardfoundational
27. Word Search II
Find all words from a dictionary in a character grid — the trie-pruned DFS Etsy's search relevance team uses to match multi-word listing titles against buyer query tokens simultaneously.
- #28hardfoundational
28. Find Median from Data Stream
Maintain a running median over a stream of numbers — Etsy's pricing analytics team uses this dual-heap pattern to track the median listing price in real time as new items are added without re-sorting.
- #1easyfoundational
1. Two Sum
Find two indices that sum to a target — Etsy's baseline hash-map check before deeper search-ranking or transaction questions.
- #2easyfoundational
2. Valid Parentheses
Validate balanced brackets using a stack — Etsy's quick screen for whether you reach for the right data structure.
- #3easyfoundational
3. Merge Two Sorted Lists
Merge two sorted linked lists into one sorted list — Etsy uses this to gauge pointer hygiene and edge-case discipline.
- #4easyfoundational
4. Remove Duplicates from Sorted Array
Compact a sorted array in-place — Etsy uses it to check whether you write O(1)-space code without leaning on a Set.
- #5easyfoundational
5. Remove Element
Strip a target value from an array in place — Etsy's quick pointer-discipline check.
- #6easyfoundational
6. Search Insert Position
Find the insertion index in a sorted array — Etsy uses it to verify clean binary-search boundaries.
- #7easyfoundational
7. Plus One
Add one to a number represented as a digit array — Etsy uses it to test carry-handling and overflow edge cases.
- #8easyfoundational
8. Merge Sorted Array
Merge nums2 into nums1 in-place using the trailing buffer — Etsy uses it to test reverse two-pointer thinking.
- #9easyfoundational
9. Binary Tree Inorder Traversal
Traverse a BST inorder iteratively — Etsy uses it to gauge whether you can simulate recursion with a stack.
- #10easyfoundational
10. Same Tree
Decide if two trees are structurally and value-wise identical — Etsy uses it to test recursion clarity.
- #11easyfoundational
11. Symmetric Tree
Check if a tree mirrors itself around the center — Etsy uses it to probe mirror-recursion fluency.
- #12easyfoundational
12. Maximum Depth of Binary Tree
Compute the longest root-to-leaf path length — Etsy uses it as a recursion-vs-BFS choice question.
- #13easyfoundational
13. Balanced Binary Tree
Decide whether a tree is height-balanced — Etsy uses it to test pruning vs. naive double-recursion.
- #14easyfoundational
14. Minimum Depth of Binary Tree
Find the shallowest leaf — Etsy uses it to test that you can choose BFS for early termination.
- #15easyfoundational
15. Pascal's Triangle
Generate the first numRows of Pascal's Triangle — Etsy uses it as a clean iteration warmup.
- #16easyfoundational
16. Best Time to Buy and Sell Stock
Maximize profit from one buy and one sell — Etsy uses it to verify single-pass min-tracking.