OpenAI Interview Questions
We track 50 interview questions reported from OpenAI: 30 in Coding & Leetcode-style Questions, 11 in System Design for ML. They average 3.5/5 difficulty — medium for a working engineer — and every one was reported by someone who sat the loop, not written by us. The topics that come up most: ml-knowledge, system-design, openai, algorithm.
Practice these on the problems board →Question mix
- Coding & Leetcode-style Questions30
- System Design for ML11
- ML Fundamentals & Algorithms5
- Deep Learning & Architectures3
- Research & Paper Understanding1
Difficulty
- 1/5 — warm-up1
- 3/5 — medium27
- 4/5 — hard19
- 5/5 — very hard3
Asked for SWE (32), MLE (22), RS (14), Infra (13)
Topics OpenAI asks about
Reported OpenAI questions
Classifier Analysis
5/5Explore the behavior of an image classification model pushed deep into the overfitting zone during extended training cycles. This advanced challenge from OpenAI tests your understanding of cross-entropy loss dynamics, gradient behavior, and performance degradation when models memorize training data completely. You will investigate mathematical shifts in confidence and error metrics as optimization continues past optimal convergence points. Access to the comprehensive breakdown and expert solution requires a paid subscription.
ML Fundamentals & AlgorithmsBattle Monsters
3/5Step into a simulated turn-based combat arena where opposing squads of creatures clash in automated warfare. Reported as an OpenAI coding challenge, this exercise evaluates your capability to structure clean object-oriented code, manage sequential event logs, and implement precise game mechanics under strict rules. You will need to handle health tracking, attack sequencing, and victory conditions efficiently. Unlock the complete problem statement and reference implementation with a subscription.
Coding & Leetcode-style QuestionsNoisy Human Data Classifier Analysis
3/5Examine the complexities of training predictive models on human-generated data fraught with hidden biases and inconsistent labeling. Featured in OpenAI interview rounds, this problem assesses your analytical capability regarding noisy annotations, specifically within identity-based text classification tasks. You will dive into how label noise impacts generalization boundaries and explore mitigation strategies for robust learning. The full problem description, analysis, and model solution are available exclusively to subscribers.
ML Fundamentals & AlgorithmsLinear Algebra (BP)
4/5Tackling distributed machine learning infrastructure, this OpenAI interview scenario requires you to implement forward and backward propagation passes for a multi-layer perceptron utilizing row-sharded weight matrices. You will work with communication primitives like collective gatherings to ensure proper synchronization across distributed nodes during gradient updates. This exercise tests your mastery of parallel tensor operations and deep learning internals. To view the full problem specifications and optimal code solution, a subscription is required.
Deep Learning & ArchitecturesToy Language Type System
3/5Design a lightweight type checker and inference engine for a custom programming language supporting primitives, tuples, generics, and higher-order functions. Encountered in OpenAI technical interviews, this task challenges your ability to build robust data structures, implement pretty-printing routines, and solve type unification algorithms effectively. You will demonstrate language design proficiency and precise pointer or reference handling. Get access to the complete problem text and verified solution by subscribing today.
Coding & Leetcode-style QuestionsTransformers Debugging
4/5Debug and optimize a miniature autoregressive transformer designed to generate sequential pixel data for digit imagery. This OpenAI interview task requires you to identify subtle implementation errors, improve training stability, and integrate a key-value cache mechanism to accelerate inference performance. It evaluates your practical familiarity with transformer architecture internals and efficient sequence generation strategies. The complete debugging guide, architectural breakdown, and verified code solution require a paid subscription.
Deep Learning & ArchitecturestransformersPython Dependency Version Compatibility Check & Adaptive Binary Search
5/5Determine the earliest compatible software version supporting a specific feature when dealing with complex, non-monotonic system behavior and hierarchical versioning strings. Reported as a challenging OpenAI interview question, this problem tests your algorithmic resourcefulness far beyond standard binary search by requiring custom adaptive strategies for erratic success criteria. You will need to optimize query counts against an unknown black-box function. Unlock the full problem details and professional implementation with a subscription.
Coding & Leetcode-style QuestionsLLM conceptual questions (Not tied with a particular company)
3/5Dive into foundational theoretical concepts underpinning modern transformer architectures and large language models. This set of conceptual questions examines computational bottlenecks, such as the quadratic time and memory complexity associated with self-attention mechanisms relative to sequence length and embedding dimensions. It is an essential review for engineers preparing for rigorous machine learning system design interviews. Access the complete conceptual overview, detailed explanations, and expert answers with a subscription.
Research & Paper UnderstandingKV Store
3/5This frequently encountered OpenAI interview problem focuses on engineering a specialized data storage mechanism that associates entries with temporal markers. Candidates must build an efficient lookup structure capable of retrieving historical values based on precise chronological queries. This exercise evaluates your understanding of temporal data organization and efficient retrieval algorithms under varying write frequencies. The full problem and model solution require a subscription.
Coding & Leetcode-style QuestionsGrid Infection and Immunity Simulation
5/5Featured in recent OpenAI technical screens, this simulation challenge tasks you with modeling the spread of contagion across a multidimensional cellular field. You will need to implement state transition logic governed by specific temporal thresholds, neighborhood dynamics, and immunity factors. The exercise tests your ability to translate complex biological or epidemic rules into clean, scalable matrix operations within strict time limits. The full problem and model solution require a subscription.
Coding & Leetcode-style Questionsdesigning iterators
4/5In this engaging OpenAI interview challenge, you are asked to design a custom traversal mechanism that can be paused and later revived from its exact previous point. The problem assesses your object-oriented design skills and your ability to serialize and restore internal traversal states cleanly without breaking standard iteration contracts. It tests advanced software engineering principles and state management techniques. The full problem and model solution require a subscription.
Coding & Leetcode-style QuestionsApplied Stats: Distributed Averaging Under Noisy Communication
4/5This applied statistics and distributed systems question, reported from OpenAI interviews, explores how networked nodes can compute collective metrics in the presence of transmission errors. You will analyze communication protocols for gathering measurements at a central aggregator while mitigating the impact of imprecise channels. The prompt evaluates your grasp of consensus concepts, statistical noise reduction, and fault-tolerant distributed algorithms. The full problem and model solution require a subscription.
ML Fundamentals & AlgorithmsMachine Trees
4/5Encounters at OpenAI often involve hierarchical network routing tasks, such as this tree-based messaging challenge. You must implement message handling routines across a distributed cluster arranged in an N-ary tree, obeying strict parent-child communication boundaries. The problem evaluates your algorithmic reasoning regarding tree traversals, recursive messaging patterns, and decentralized coordination. The full problem and model solution require a subscription.
Coding & Leetcode-style QuestionsIP to CIDR
3/5Reported as an OpenAI coding challenge, this problem investigates how internet protocol addresses can be sequentially traversed and compressed into efficient routing blocks. You will work with bitwise representations, range aggregations, and scalable iteration patterns suitable for massive address spaces. The task tests your bit manipulation proficiency and ability to optimize network block calculations. The full problem and model solution require a subscription.
Coding & Leetcode-style QuestionsChatbot Code Refactoring
3/5This reported OpenAI interview challenge asks you to clean up a messy, monolithic conversational script into a modular and extensible object-oriented architecture. Candidates must restructure the codebase to support various messaging spaces and distinct conversational agents while maintaining backward compatibility with legacy hooks and passing all pre-existing unit tests. This task evaluates your software engineering best practices, design pattern application, and code maintainability in a production environment. Access to the complete problem breakdown and expert model solution requires an active subscription.
System Design for MLML Debugging (Transformer)
4/5This OpenAI interview question plunges you into a PyTorch-based autoregressive transformer containing intentionally hidden software defects. Your mission is to diagnose and resolve errors spanning attention mechanisms, positional embedding initialization, and loss computation pathways during causal sequence modeling. This troubleshooting task measures your practical familiarity with modern deep learning architectures and tensor manipulation debugging. View the complete problem text, bug analysis, and verified correction code by becoming a subscriber.
Deep Learning & ArchitecturesResumable Iterator
4/5Featured in recent OpenAI interview rounds, this algorithmic problem challenges you to build a specialized wrapper class that brings state persistence to standard iterators and generators. You will need to implement mechanisms for tracking traversal progress, serializing the internal cursor, and seamlessly resuming iteration from any previously saved checkpoint. This exercise assesses your grasp of advanced control flow, state management, and Python iterator protocols. Gain access to the comprehensive problem specifications and optimal reference solution by subscribing today.
Coding & Leetcode-style QuestionsiteratorIterative data mining & model training for multi modality foundation model training
4/5In this system design challenge reported at OpenAI, you must architect a large-scale data curation and machine learning pipeline to filter massive, noisy interaction logs for multimodal foundation models. The assignment explores automated data cleansing, quality bootstrapping, and iterative refinement strategies to transform raw, uncurated user behavior into high-grade training sets. It examines your ability to handle noisy data distributions and design robust training loops for advanced artificial intelligence agents. Unlock the complete architectural breakdown and expert solution by subscribing.
System Design for MLsystem designSocial Network with Immutable Snapshots + Followers Index + Recommendations
3/5Encountered during OpenAI interview sessions, this data structures and algorithms question requires you to design an in-memory social networking graph supporting historical point-in-time snapshots. You will implement mechanisms to handle directed relationships, generate immutable topology records, and efficiently query historical connection states and recommendations. This exercise tests your proficiency with graph manipulation, memory efficiency, and temporal data modeling. Access the full problem description and optimal algorithmic solution with a subscription.
Coding & Leetcode-style QuestionsSimulating Particle Hits on an Infinite Screen
4/5Explore this challenging probability and mathematical modeling exercise recently featured in technical evaluations at OpenAI. The problem requires candidates to analyze the geometric distribution of particle trajectories emitted from a central point toward an infinite boundary. It tests your ability to apply statistical distributions, compute spatial intersections, and translate physical phenomena into rigorous mathematical formulations. Unlocking the complete problem statement, deep analytical breakdown, and optimized model solution requires an active subscription.
ML Fundamentals & AlgorithmsProblem: CI/CD Job Scheduler Design using Kubernetes and Docker
3/5Engage with a scalable system design challenge inspired by infrastructure interviews at OpenAI, focusing on building a robust continuous integration and deployment scheduler. You will design an architecture leveraging containerization and orchestration tools to handle declarative pipeline definitions, manage job queues securely across multi-tenant environments, and ensure fault-tolerant execution. To examine the comprehensive system requirements, architectural diagrams, and expert design solutions, please subscribe.
System Design for MLDesign a Crossword Puzzle Solver
3/5Solve an intricate constraint satisfaction puzzle reported from engineering interviews at OpenAI. The challenge requires designing an automated solver that takes a partially filled grid and a lexicon of valid terms to reconstruct a complete, rule-abiding puzzle board. It tests your expertise in recursive backtracking algorithms, search space pruning, and state management. Unlocking the full problem specification, complexity analysis, and complete reference implementation requires an active subscription.
System Design for MLDistributed Machine Cluster Count
4/5Featured in OpenAI software engineering interviews, this distributed systems challenge revolves around analyzing a machine cluster arranged in a tree hierarchy. You must design recursive or message-passing algorithms to compute the total node count and map out the entire network topology using only local neighbor communication. This problem tests your mastery of graph traversal, tree properties, and distributed coordination. To read the complete problem breakdown, architectural considerations, and model solutions, a subscription is required.
Coding & Leetcode-style QuestionsBalanced Tag-Pair Sequence
1/5This OpenAI interview question asks you to construct a balanced sequence of content pairs subject to strict prefix constraints across multiple categories. The task evaluates your combinatorial reasoning, algorithmic thinking, and ability to maintain structural invariants dynamically. It is an excellent test of fine-grained sequence generation and constraint management. Unlock the complete problem specification and optimal algorithmic solution by purchasing a subscription.
Coding & Leetcode-style QuestionsReliable LLM evaluation pipeline
3/5Reported as an OpenAI interview task, this question centers on engineering a robust internal pipeline for model evaluation, covering inference restart policies, memory-constrained entropy calculations, and fair annotation assignment. It tests your capability to apply probability bounds, optimize memory footprints, and manage complex distributed resources reliably. To explore the full problem architecture, mathematical proofs, and complete solution code, a subscription is required.
ML Fundamentals & AlgorithmsIn-Memory Rate Limiter
3/5This coding challenge, featured in OpenAI technical screenings, requires candidates to build a thread-safe traffic throttling utility that evaluates whether incoming calls should pass based on specific time-window rules. It tests concurrency management, state maintenance under high load, and algorithmic efficiency in a multithreaded environment. Access to the complete problem breakdown and verified solution code requires an active subscription.
Coding & Leetcode-style QuestionsGPU Credits 2
3/5Encountered in software engineering interviews at OpenAI, this hard-level design exercise challenges applicants to manage a resource ledger involving timed allocations and sequential deductions. Candidates must efficiently track expiration timelines, update balances dynamically, and optimize data retrieval using advanced heap and greedy strategies. To view the comprehensive problem statement and reference implementation, a paid subscription is necessary.
Coding & Leetcode-style QuestionsImplement a Unix-like `cd` Command (with Symlink Follow-up)
3/5Featured in OpenAI interview sessions, this coding problem requires engineering a path resolution utility that mimics standard directory navigation behavior, including relative routing and symbolic link handling. It evaluates string manipulation, tree traversal logic, and edge-case management in file system representations. The comprehensive problem description and optimal coding solution are restricted to subscribers.
Coding & Leetcode-style QuestionsImplement an in-memory TTL cache (optionally LRU)
3/5In this reported OpenAI interview question, you are asked to design and implement an in-memory caching system featuring time-to-live expiration semantics. The exercise tests your ability to handle data retention rules, optimize retrieval performance, and manage eviction behavior efficiently. You will need to choose appropriate internal data structures to handle expiration thresholds and updates gracefully while maintaining optimal time complexity. Access to the full problem breakdown and the optimal model solution requires a subscription.
Coding & Leetcode-style QuestionsDesign a hosted notebook platform for interactive code execution
4/5In this reported OpenAI system design question, you are tasked with architecting a cloud platform capable of hosting interactive code execution notebooks for hundreds of thousands of concurrent users. The problem assesses your ability to scale isolated container environments, manage workspace lifecycles, handle persistent storage, and implement quick suspension and resumption mechanisms. You will need to design robust communication layers and resource allocation strategies for heavy interactive workloads. The detailed system requirements and comprehensive solution architecture require a subscription.
System Design for MLsimulate the change directory command
3/5This string simulation challenge, reported from OpenAI interviews, asks you to write a command-line utility that mimics a terminal navigation tool. You must correctly process both relative and absolute path modifications, handle parent directory jumps, and gracefully manage edge cases like malformed paths or going past the root directory. The exercise evaluates your command of string parsing, state tracking, and stack data structures. Gain full access to the problem requirements, test cases, and clean code solution with a subscription.
Coding & Leetcode-style QuestionsStreaming Entropy (Numerical Stability + Online Accumulation)
3/5Compute the statistical entropy of a softmax probability distribution while avoiding catastrophic numerical underflow or overflow in this algorithmic challenge reported from OpenAI. You will first implement a stable batch calculation using logarithmic shifting techniques and then extend your solution to handle a streaming data architecture where inputs arrive sequentially and metrics update in an online fashion. Access the complete problem specification, mathematical breakdown, and model solution with a subscription.
Coding & Leetcode-style Questionsnumerical-stabilitystreamingml-knowledgeDesign a GPU Scheduling Platform
4/5This reported OpenAI interview challenge asks you to architect a cluster management platform capable of distributing limited hardware resources across competing machine learning workloads. You will need to address priority queues, topology-aware placement for multi-node tasks, failure recovery, and strategies to balance hardware utilization against queue wait times. The complete breakdown and expert architectural solution require a subscription.
System Design for MLsystem-designschedulinggpuSystem Design: Chess Game
3/5This reported OpenAI system design challenge focuses on building the backend infrastructure for a real-time multiplayer chess platform similar to Chess.com. You will be expected to handle user matchmaking based on Elo ratings, maintain synchronized WebSocket connections for gameplay, validate moves securely on the server, and manage precise chess clocks. The complete system design breakdown and reference architecture require a subscription.
System Design for MLDesign ChatGPT: A Conversational LLM Serving Platform
4/5Explore how to architect a real-time conversational intelligence service capable of streaming text generation to massive concurrent user bases. This OpenAI reported system design challenge evaluates your ability to manage expensive hardware accelerators, handle memory efficiently through KV caching techniques, and maintain multi-turn dialogue state under strict latency bounds. You will learn strategies for continuous batching and request prioritization. The full problem and model solution require a subscription.
System Design for MLsystem-designllminferenceDesign a Distributed Training Platform for Foundation Models
4/5Architect a massive, highly available distributed infrastructure designed to train giant foundation models across thousands of accelerators simultaneously, as featured in an OpenAI system design interview. This problem focuses on orchestrating synchronous workloads, handling rapid fault recovery, optimizing data pipelines, and managing model parallelism strategies like tensor and pipeline sharding. You will also tackle scheduling fairness and network bottlenecks. Unlock the full design breakdown and expert architectural solution with a subscription.
System Design for MLsystem-designtraininggpuData Labeling Task Scheduler
3/5Designed around a complex scheduling scenario reported at OpenAI, this coding task requires building a fair allocation engine for multi-party workflows involving models, humans, and specific tasks. You will implement robust distribution logic that satisfies strict quota limits, workload balancing thresholds, and uniqueness constraints across various participation phases. This problem thoroughly tests advanced greedy allocation, state management, and constraint satisfaction techniques. Access to the full problem text and complete model solution requires a subscription.
Coding & Leetcode-style QuestionsalgorithmsimulationschedulingModalLock and FairModalLock
4/5Explore advanced concurrency concepts with this Python synchronization problem frequently utilized in machine learning infrastructure interviews at OpenAI. You are tasked with implementing specialized locking primitives that manage thread access across distinct operational modes while preventing thread starvation through FIFO fairness guarantees. This exercise examines your mastery of low-level concurrency controls, condition variables, and thread coordination. Unlock the complete problem specifications and the reference model solution with a paid subscription.
Coding & Leetcode-style QuestionsconcurrencythreadingpythonCode Reading — 400-line PyTorch Refactor
3/5This code reading evaluation from OpenAI requires candidates to analyze, refactor, and extend a substantial PyTorch codebase centered around noisy classifier architectures. Instead of building from scratch, engineers must quickly orient themselves within an unfamiliar project, evaluate time and space complexities of tensor operations, and implement structural enhancements. Success demonstrates strong codebase navigation and advanced deep learning framework proficiency. Explore the complete codebase analysis and model refactoring steps with a paid subscription.
Coding & Leetcode-style Questionscode-readingpytorchDesign an AI Chatbot App (RAG-Grounded Assistant)
4/5Learn to architect an enterprise-grade document assistant that retrieves verified knowledge to provide accurate responses with proper source attribution. In this reported OpenAI design scenario, you will examine ingestion pipelines, chunking strategies, vector index maintenance, and prompt assembly techniques designed to minimize hallucination. The architecture focuses heavily on grounding generative models with proprietary corporate data. The full problem and model solution require a subscription.
System Design for MLsystem-designllmragIn-Memory Database with SQL Operations
3/5Reported during technical interviews at OpenAI, this coding task requires building an in-memory database that handles fundamental query processing operations directly through native method calls rather than parsing raw text strings. Developers must progressively implement core features such as table creation, record insertion, column projection, conditional filtering, and sorted output, followed by an architectural discussion on indexing optimizations. Unlock the full problem description, edge case analyses, and a complete model solution by purchasing a site subscription.
Coding & Leetcode-style Questionsin-memory-databasesqldata-structureAutograd / Manual Backprop + Hillis-Steele Scan
3/5Dive into deep learning internals by implementing custom automatic differentiation and parallel scan algorithms, as seen in technical evaluations at OpenAI. You will compute inclusive prefix products and construct manual backward passes for matrix sequences before optimizing the workflow using log-depth parallel techniques. This task evaluates your understanding of gradient propagation, tensor operations, and parallel computing paradigms. Unlock the complete problem requirements and the optimal model solution through our paid subscription.
Coding & Leetcode-style Questionsml-knowledgeautogradscanMath Reasoning: Stopping Time / Las Vegas Algorithm
4/5Examine a sophisticated probability and stochastic reasoning challenge frequently asked in OpenAI technical interviews, focusing on optimizing randomized algorithms through strategic timeout designs. This exercise evaluates your mastery of mathematical bounds, expected value calculations, and restart strategies to minimize completion times for probabilistic tasks under uncertainty. It tests theoretical reasoning rather than raw programming skill. The complete analytical breakdown and expert solutions require a paid subscription.
Coding & Leetcode-style Questionsml-knowledgemath-reasoningprobabilityNumPy Puzzle: 1-NN Vectorization → Wx+b Network
3/5Master high-performance matrix operations and spatial classification techniques inspired by coding evaluations at OpenAI. This exercise challenges practitioners to implement distance-based prediction logic entirely through vectorized array manipulations, avoiding standard iteration loops, before translating the identical procedure into a neural network forward propagation framework. Learn how to leverage advanced mathematical libraries for optimal efficiency by accessing the full problem breakdown and expert solution.
Coding & Leetcode-style Questionsml-knowledgenumpylinear-algebraMemory Allocator
4/5Featured in OpenAI interview rounds, this systems programming problem requires engineering an efficient memory allocation and deallocation manager. Candidates must avoid naive linear scans and design a data structure that handles fixed-capacity resource allocation and release operations with optimal time complexity. The task tests deep understanding of memory management algorithms, pointer arithmetic, and data structure selection for performance-critical applications. Reviewing the full problem requirements and complete model solution necessitates a subscription.
Coding & Leetcode-style Questionsalgorithmdata-structureoop-designOpenSheet: Spreadsheet with Cell Dependencies
3/5In this coding interview question reported at OpenAI, you are asked to build a mini spreadsheet application that manages cell references, mathematical formulas, and automatic dependency updates. The challenge requires handling arithmetic operations while detecting and preventing circular references among cell links, with follow-ups exploring optimized evaluation graphs. It tests your graph traversal algorithms, state management, and object-oriented design capabilities. Access to the complete problem breakdown and verified model solution requires a subscription.
Coding & Leetcode-style Questionsgraphdfstopological-sortIP Address / CIDR Iterator
3/5Design a robust network address iterator capable of parsing IP ranges and CIDR blocks while supporting bi-directional traversal and membership checks, featured in interviews at OpenAI. The problem unfolds incrementally through multiple implementation stages, testing your ability to handle boundary conditions, numerical conversions, and iterator protocols cleanly. It evaluates your knack for writing modular, self-consistent code that scales with evolving requirements. Read the full multi-part problem description and examine the clean solution code with a subscription.
Coding & Leetcode-style Questionsalgorithmstringbit-manipulationShard Rebalance / Overlapping Key Range
3/5Solve a distributed systems puzzle focusing on dynamic range allocation and shard rebalancing, highlighted in recent engineering interviews at OpenAI. Your task involves maintaining a collection of keyed intervals, handling insertions and deletions, and executing a rebalance routine to cap maximum overlaps while minimizing data movement. This problem challenges your algorithmic thinking regarding interval sorting, gap filling, and efficient resource partitioning. Access the full problem details and expert solution architecture by subscribing today.
Coding & Leetcode-style QuestionsalgorithmintervalsimulationDurable Key-Value Store Serialization
3/5Design a resilient persistence layer with custom serialization rules in this compelling challenge inspired by OpenAI technical interviews. The exercise tests your ability to encode arbitrary data structures containing complex characters directly into binary formats without relying on standard built-in serializers, while also handling strict file size constraints. Gain immediate access to the complete problem description and model code by subscribing.
Coding & Leetcode-style QuestionsiofilesystempersistenceDistributed Device Control
4/5System Design for ML
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OpenAI interview FAQ
- How many OpenAI interview questions are available?
- 50 reported OpenAI questions, the largest group being Coding & Leetcode-style Questions (30).
- How hard is the OpenAI interview?
- Across the questions we track, OpenAI averages 3.5 out of 5: 1 at 1/5, 27 at 3/5, 19 at 4/5, 3 at 5/5.
- What topics does OpenAI ask about?
- Most often ml-knowledge, system-design, openai, algorithm, gpu.