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Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
- 9403
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 121–150 of 9403 results
- AirbnbMediumData ScientistCompute C/T metrics from bookings and visits
This question evaluates time-window attribution, visit deduplication, control vs treatment metric computation, aggregation of conversions and revenue, and statistical interval estimation (Wilson CIs), testing practical data manipulation skills with SQL or Python in the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Technical Screen - AirbnbMediumSoftware EngineerCompute board-game score from regions
This problem tests your ability to identify connected components in a 2D grid using graph traversal (BFS/DFS) and aggregate properties associated with those components.
Coding & AlgorithmsOnsiteGraph TraversalBFSDFS - AirbnbMediumData ScientistCompute browsing metrics in Python from logs
This question evaluates a candidate's ability to perform event-level data manipulation and analytics in Python and SQL, covering sessionization, time-zone–consistent timestamp handling, deduplication, funnel construction, segment-level aggregation, conversion-rate computation, and statistical confidence intervals such as the Wilson CI.
Data Manipulation (SQL/Python)Technical Screen - AirbnbMediumSoftware EngineerCompute minimum-cost service cover
This question evaluates proficiency in combinatorial optimization and set-coverage with cost minimization, including handling case-insensitive service matching and enumerating minimal solution combinations.
Coding & AlgorithmsTechnical Screen - AirbnbMediumSoftware EngineerCompute split-stay listing pairs
This question evaluates the ability to manipulate interval availability data, reason about contiguous date ranges and split boundaries, and design efficient pairing algorithms with attention to time and space complexity.
Coding & AlgorithmsTechnical Screen - AirbnbMediumSoftware EngineerConstruct smallest number from I/D pattern
This problem tests greedy algorithm design and stack-based data structure manipulation to satisfy relative ordering constraints within a sequence of digits.
Coding & AlgorithmsTechnical ScreenGreedyStackStrings - AirbnbMediumSoftware EngineerCount Candies from Unlockable Boxes
Determine the maximum number of candies you can collect given an initial set of boxes, where each box may be locked or unlocked, contain candies, contain keys to other boxes, and contain other boxes.
Coding & AlgorithmsTechnical ScreenBreadth-First SearchGraphQueue - AirbnbHardSoftware EngineerCount Consecutive Positive Integer Sums
Count representations of a positive integer as one or more consecutive positive integers, including the one-term representation. Derive the arithmetic condition for each sequence length and use a square-root bound rather than testing every possible starting value.
Coding & AlgorithmsOnsite - AirbnbMediumData ScientistDefine Success Metrics and Experiment Plan for Product Development
Evaluates product-planning metrics and experiment design for a two-sided marketplace booking funnel. Strong answers define a primary booking metric, diagnostic and guardrail metrics, randomization unit, sample size, marketplace spillovers, and launch criteria before development.
Analytics & ExperimentationTechnical Screen - AirbnbMediumSoftware EngineerDefine a File Store with User Quotas and Compression
Implement an in-memory cloud file store that supports file creation, copying, prefix/suffix search, per-user storage quotas, and atomic file compression/expansion.
Software Engineering FundamentalsOnline AssessmentData StructuresDesignString - AirbnbMediumData ScientistDescribe How You Use SQL in Data Science Work
This question assesses a candidate's ability to articulate their technical workflow in SQL, focusing on data extraction strategies, quality assurance, and how technical analysis translates into business impact.
Data Manipulation (SQL/Python)HR ScreenSQLData ScienceAnalytics - AirbnbMediumSoftware EngineerDescribe a cross-functional project you’re proud of
This question evaluates cross-functional collaboration, leadership, stakeholder alignment, conflict resolution, project ownership, and the ability to articulate technical and product decisions along with measurable impact.
Behavioral & LeadershipOnsite - AirbnbMediumSoftware EngineerDescribe a flagship project’s architecture and tradeoffs
This question evaluates leadership and ownership along with system architecture and trade-off analysis, assessing competencies in end-to-end technical design, stakeholder communication, implementation decisions, and metrics-driven impact.
Behavioral & LeadershipOnsite - AirbnbMediumSoftware EngineerDescribe your role, motivations, and values
This question evaluates a software engineer's communication, self-awareness, motivation, and cultural-fit competencies, along with indicators of leadership, teamwork, and clarity in scope and impact.
Behavioral & LeadershipHR Screen - AirbnbMediumMachine Learning EngineerDesign User Embedding Semantic Search
This question evaluates competency in ML system design for recommendation and semantic retrieval, covering user and listing representation learning, two-stage retrieval and ranking architectures, training objectives and label design, bias correction from interaction logs, and evaluation and experimentation practices.
ML System DesignOnsite - AirbnbMediumMachine Learning EngineerDesign a Family-Friendly Listing Classifier
This question evaluates proficiency in machine learning system design, including problem formulation tied to product objectives, labeling strategy, feature engineering, model selection, evaluation metrics, robustness to adversarial labels, fairness considerations, and cold-start handling.
ML System DesignOnsite - AirbnbMediumSoftware EngineerDesign a Multi-Level In-Memory Cloud Storage Service
Design a multi-tiered in-memory cloud storage system supporting staged uploads, capacity limits, prefix search ranking, and conflict-aware backup and restore operations.
Software Engineering FundamentalsOnline AssessmentDesignData StructuresHash Table - AirbnbMediumSoftware EngineerDesign a Reliable Scheduler for Payment Jobs
Tests candidate's ability to design a mission-critical, fault-tolerant job scheduler for payment processing, focusing on lease claiming, idempotency, race condition handling, and reconciliation.
System DesignOnsitesystem-designdistributed-systemspayments - AirbnbHardBackend EngineerDesign a Rental Marketplace Backend
This problem tests your ability to design a distributed, high-scale rental marketplace platform, focusing on concurrency control for bookings, efficient geo-spatial searching, and data consistency.
System DesignOnsiteDistributed SystemsConcurrencyGeo-spatial - AirbnbMediumSoftware EngineerDesign a Stateful Banking System with Scheduled Payments and Account Merges
Design an in-memory stateful banking system that supports account creation, transfers, spending leaderboards, scheduled payments with deterministic backlog processing, and account merges.
Software Engineering FundamentalsOnline Assessmentdata-structuresheapsystem-simulation - AirbnbHardSoftware EngineerDesign a Stateful Working Hours Register
Design an in-memory working hours and compensation tracking register that supports badge events, top-k leaderboards, scheduled rate changes, and interval-based historical earnings calculations.
Software Engineering FundamentalsOnline AssessmentDesignIntervalsBinary Search - AirbnbMediumSoftware EngineerDesign a banking ledger for deposits/withdrawals
This question tests your ability to design a robust database schema and service logic for a banking system, focusing on data integrity, transaction atomicity, and handling high-concurrency balance updates.
Software Engineering FundamentalsTechnical ScreenDatabase DesignConcurrencyTransactions - AirbnbMediumSoftware EngineerDesign a booking system
This question tests the ability to design a distributed reservation system that handles high concurrency, prevents double-booking, and ensures data consistency at scale.
System DesignOnsiteConcurrencyDatabaseDistributed Systems - AirbnbHardSoftware EngineerDesign a dynamic rental pricing system
This question evaluates skills in production machine learning system design for pricing, including problem formulation, data and feature engineering, modeling and uncertainty management, online inference and scalability, experimentation and guardrails, and considerations like fairness and cold-start handling.
ML System DesignOnsite - AirbnbHardSoftware EngineerDesign a fast host listing metrics page
This question evaluates backend system design and data engineering competencies, including scalable API design, time-range aggregation correctness (handling partial overlaps and state changes), data modeling and indexing, caching and precomputation, and performance validation.
System DesignTechnical Screen - AirbnbHardSoftware EngineerDesign a group chat system
Airbnb's onsite system design round asks you to design the backend for a real-time group chat and messaging system: 1:1 and group conversations, near-real-time delivery, accurate unread counts, and full paginated history at roughly 1B messages a day and 5M concurrent connections. A complete answer covers the guarantees, APIs, data model and partitioning, write path and ordering, WebSocket fan-out and presence, offline delivery and multi-device sync, unread counts, membership changes, failure modes and observability. This walkthrough gives a corrected end-to-end reference answer for every part, including the trade-offs interviewers probe.
System DesignOnsite - AirbnbHardSoftware EngineerDesign a hot-listing waitlist API
Design a hot-listing waitlist API evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnsite - AirbnbHardSoftware EngineerDesign a multi-channel notification system
This question tests the ability to design a distributed, multi-channel notification system capable of handling high throughput, varying latency requirements across channels (e.g., email, push, SMS), and ensuring reliable message delivery.
System DesignTechnical ScreenDistributed SystemsScalabilityMessage Queues - AirbnbMediumData ScientistDesign a network-aware Wi‑Fi badge experiment
This question evaluates a data scientist's proficiency in experimental design, causal inference under interference (including SUTVA risks), metric specification, power and sample‑size computation, analysis planning, and translating treatment effects into financial decision rules.
Analytics & ExperimentationTechnical Screen - AirbnbHardSoftware EngineerDesign a real-time chat system with hot groups
This problem tests your ability to design a distributed, low-latency messaging system that handles massive fan-out and identify trending group activities.
System DesignOnsiteDistributed SystemsWebSocketsCaching
Airbnb