HubSpot Coding Interview Questions
25 HubSpot coding interview problems with full optimal solutions — 8 easy, 12 medium, 5 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an HubSpot interviewer values, and a FAQ section.
Showing 7 problems of 25
- #1easyfrequently asked
1. Two Sum
HubSpot uses Two Sum as a warm-up screen to see if you can jump straight from brute force to an O(n) hash-map solution while explaining your reasoning out loud — a habit their Boston engineering culture values deeply.
- #20easyfrequently asked
20. Valid Parentheses
HubSpot asks Valid Parentheses to test stack intuition and edge-case discipline — skills that surface constantly when parsing template syntax, email tokens, or workflow expression strings in their CRM platform.
- #21easyfrequently asked
21. Merge Two Sorted Lists
HubSpot asks Merge Two Sorted Lists to evaluate pointer hygiene and recursive vs. iterative trade-offs — skills that translate directly to merging ordered event streams and sorted activity logs in their CRM timeline features.
- #53easyfrequently asked
53. Maximum Subarray
HubSpot asks Maximum Subarray to test Kadane's algorithm — one of the most elegant greedy/DP hybrids in the canon — and to see whether you can clearly articulate why dropping a negative prefix always improves the running sum.
- #70easyfrequently asked
70. Climbing Stairs
HubSpot uses Climbing Stairs as an entry point into dynamic programming thinking — they want to see you recognize overlapping subproblems and memoize rather than recompute, a discipline that directly applies to their complex workflow-evaluation engines.
- #121easyfrequently asked
121. Best Time to Buy and Sell Stock
HubSpot includes this classic sliding-window / greedy problem to test whether you can track a running minimum while computing a maximum difference — a pattern that recurs in revenue-trend analysis across their sales CRM data pipelines.
- #206easyfrequently asked
206. Reverse Linked List
HubSpot includes Reverse Linked List to confirm you can manipulate pointer-based structures precisely — an essential skill for engineers working on their pipeline and activity-feed data models where ordered traversal matters.
Related interview-prep guides
SEO Interview Questions for 2026: 30+ Questions Across Technical SEO, On-Page, Links, Content, and Analytics
SEO interview questions in 2026 test more than knowing what a meta description is. Hiring managers probe how you debug a crawl-budget bleed, how you defend an AI-generated content audit, how you read a Search Console drop, and whether you can talk attribution to a CMO without losing the room. This guide covers 30+ questions across five categories plus the marketing-grad-specific prep plan.
Sensei AI Alternatives in 2026: 6 Tools Compared (Interview + Sales Coaching)
Sensei AI is a real-time speech-coaching overlay built for sales calls and meetings, not for job interviews. Sales reps and SDR candidates keep trying it for interview prep and hitting three walls: latency on long-form behavioral answers, no resume-aware context, and a meeting-minute cap that runs out mid-loop. This guide compares 6 alternatives split into interview-focused and meeting-focused tools, with honest notes on where each one wins and where each one breaks. Built for the SDR-candidate-turned-interview-prepper avatar, not the enterprise sales-enablement buyer.