OpenAI interview practice
Practice from 81 OpenAI-tagged public coding problems, organized only by the stage, topic, difficulty, and recency metadata FastPrep can verify. The broader public catalog also includes 21 system-design exercises, 2 low-level-design exercises, 1 project-coding exercise.
OA practice path
Build a timed implementation rhythm from prompt to edge cases. Problems are ranked by repeated public catalog sightings.
| Company | Problem | Difficulty | Public evidence | Action |
|---|---|---|---|---|
OPOpenAI | Network Endpoint or Cycle BoundaryGraphHash Table | Easy | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Leaves Remaining After Wind GustsMatrixSimulation | Medium | 3 public reportsLast reported Sep 2026 | Practice |
OPOpenAI | Longest Increasing Price SubsequenceArrayBinary Search | Medium | 2 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Simplify a Quadratic ExpressionStringParsing | Medium | 2 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Minimum-Cost Color SequenceArrayDynamic Programming | Medium | 2 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Count Routes Through Four Shop TypesGraphDynamic Programming | Medium | 2 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Largest Microorganism After ConsumptionArraySimulation | Medium | 2 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Macaron Order PriceArraySorting | Medium | 1 public reportLast reported Oct 2026 | Practice |
OPOpenAI | Shortest Atom Action PathMatrixBreadth-First Search | Medium | 1 public reportLast reported Oct 2026 | Practice |
OPOpenAI | Invert or Blur an ImageMatrixSimulation | Easy | 1 public reportLast reported Sep 2026 | Practice |
OPOpenAI | Optimal First-Player Card ScoreArrayDynamic Programming | Medium | 1 public reportLast reported Sep 2026 | Practice |
OPOpenAI | Largest Square of OnesArrayMatrix | Medium | 1 public reportLast reported Sep 2026 | Practice |
OPOpenAI | Repair One Movement InstructionMatrixString | Medium | 1 public reportLast reported Sep 2026 | Practice |
OPOpenAI | Cogwheel Rotation DirectionsGraphBreadth-First Search | Medium | 1 public reportLast reported Mar 2026 | Practice |
OPOpenAI | Digit-Sum Sequence Join PointMathTwo Pointers | Easy | 1 public reportLast reported Mar 2026 | Practice |
OPOpenAI | Minimum Dining Table RotationsDynamic ProgrammingArray | Medium | 1 public reportLast reported Mar 2026 | Practice |
OPOpenAI | Count Valid SequencesDynamic ProgrammingHash Table | Medium | 1 public reportLast reported Jan 2025 | Practice |
OPOpenAI | Count Matching Regions in Two Binary GridsMatrixGraph | Medium | 1 public reportLast reported Oct 2024 | Practice |
OPOpenAI | Maximize Wall HitsDynamic ProgrammingGreedy | Hard | 1 public reportLast reported Sep 2024 | Practice |
OPOpenAI | Largest Square Subgrid Under a Sum LimitMatrixPrefix Sum | Medium | 1 public reportLast reported Dec 2021 | Practice |
Phone practice path
Practice solving while explaining assumptions, tradeoffs, and complexity. Problems are ranked by repeated public catalog sightings.
54 OpenAI-tagged Phone Screen problems available.
| Company | Problem | Difficulty | Public evidence | Action |
|---|---|---|---|---|
OPOpenAI | Sparse Plant Infection SimulationSimulationHash Table | Hard | 12 public reportsLast reported Sep 2026 | Practice |
OPOpenAI | Versioned Social NetworkDesignHash Table | Hard | 11 public reportsLast reported Aug 2026 | Practice |
OPOpenAI | GPU Credit LedgerDesignSimulation | Hard | 10 public reportsLast reported Sep 2026 | Practice |
OPOpenAI | Plant Infection Simulation, Part 4: Death CountdownMatrixSimulation | Hard | 5 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Aggregate Machine TopologyTreeGraph | Medium | 5 public reportsLast reported Sep 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 1: Batch EntropyArrayMath | Easy | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 2: Numerically Stable EntropyArrayMath | Medium | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 3: Block-wise EntropyArrayMath | Medium | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 4: Stable Streaming EntropyArrayMath | Hard | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Prefix Matrix Products and AutogradMatrixPrefix Sum | Hard | 4 public reportsLast reported Sep 2026 | Practice |
OPOpenAI | Versioned Followers and FolloweesDesignGraph | Medium | 4 public reportsLast reported Aug 2026 | Practice |
OPOpenAI | Poker Deal and Hand-Winner SimulationSimulationSorting | Hard | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Segmented Durable Key-Value StoreDesignHash Table | Medium | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Network Endpoint or Cycle BoundaryGraphHash Table | Easy | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Memory AllocatorDesignIntervals | Medium | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Durable Work Queue OperationsHash TableQueue | Hard | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Versioned Friend RecommendationsGraphBinary Search | Hard | 3 public reportsLast reported Aug 2026 | Practice |
OPOpenAI | Resumable List IteratorArrayDesign | Medium | 3 public reportsLast reported Jun 2026 | Practice |
OPOpenAI | Evaluate Noisy AnnotatorsArraySimulation | Medium | 2 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Durable Work Queue with DependenciesDesignQueue | Hard | 2 public reportsLast reported Oct 2026 | Practice |
Onsite practice path
Practice complete solutions and defend the choices behind them. Problems are ranked by repeated public catalog sightings.
| Company | Problem | Difficulty | Public evidence | Action |
|---|---|---|---|---|
OPOpenAI | Sparse Plant Infection SimulationSimulationHash Table | Hard | 12 public reportsLast reported Sep 2026 | Practice |
OPOpenAI | Versioned Social NetworkDesignHash Table | Hard | 11 public reportsLast reported Aug 2026 | Practice |
OPOpenAI | GPU Credit LedgerDesignSimulation | Hard | 10 public reportsLast reported Sep 2026 | Practice |
OPOpenAI | Plant Infection Simulation, Part 4: Death CountdownMatrixSimulation | Hard | 5 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 1: Batch EntropyArrayMath | Easy | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 2: Numerically Stable EntropyArrayMath | Medium | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 3: Block-wise EntropyArrayMath | Medium | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Streaming Entropy, Part 4: Stable Streaming EntropyArrayMath | Hard | 5 public reportsLast reported Jul 2026 | Practice |
OPOpenAI | Segmented Durable Key-Value StoreDesignHash Table | Medium | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Durable Work Queue OperationsHash TableQueue | Hard | 3 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | Count Friend CirclesGraphDepth-First Search | Medium | 2 public reportsLast reported Oct 2026 | Practice |
OPOpenAI | GPU Credit Ledger with a Negative-Balance Failure StateDesignSimulation | Hard | 1 public reportLast reported Sep 2026 | Practice |
OPOpenAI | Iterate Canonical IPv6 AddressesStringMath | Medium | 1 public reportLast reported Sep 2026 | Practice |
OPOpenAI | 15-Minute Chat Session TrackerHash TableSliding Window | Hard | 1 public reportLast reported Jul 2026 | Practice |
OPOpenAI | Tensor-Parallel MLP GradientsArrayMatrix | Hard | 1 public reportLast reported Jul 2026 | Practice |
OPOpenAI | Message Event AggregationHash TableSliding Window | Medium | 1 public reportLast reported Jul 2026 | Practice |
OPOpenAI | DSA Round: Maximum Score Grid PathDynamic ProgrammingMatrix | Hard | 1 public reportLast reported May 2026 | Practice |
OPOpenAI | Convert an IPv4 Range to Minimal CIDR BlocksStringBit Manipulation | Medium | 1 public reportLast reported Oct 2025 | Practice |
OPOpenAI | Toy Language Generic Return-Type InferenceStringParsing | Hard | 1 public reportLast reported Mar 2025 | Practice |
01 · Stage workflow
The current public inventory is phone-screen heavy and also contains design practice, so rehearse clear reasoning aloud alongside implementation and architecture work. Your invitation and recruiter guidance remain the source of truth.
Use the timing and format in your invitation as the source of truth. In practice, work without interruptions, budget time to read constraints, and reserve a final review window for boundary cases.
Treat the problem as a conversation. Clarify the contract, describe the approach before implementation, and keep narrating meaningful decisions while you code and test.
Use the catalog's onsite labels as practice context, not as a promise about a specific loop. Focus on collaborative problem solving: compare approaches, implement cleanly, and explain how the solution behaves at scale.
02 · Broader technical practice
These public OpenAI-tagged exercises cover additional technical formats. They are included only when a verified catalog record and a crawlable practice page both exist.
Design a payment lifecycle that durably accepts hold and charge work, resolves upstream outcomes, releases unused holds, and incrementally builds parallel network-specific settlement batches.
Open practiceDesign a real-time typing race with matchmaking, authoritative progress, wrong-letter freezes, latency-aware winner selection, and durable rankings.
Open practiceServe versioned large models on shared accelerators with shard-aware scheduling, continuous batching, bounded admission, streaming recovery, stable experiments, and safe fallback or rollback.
Open practiceDesign a reliable payment path that turns an order into one captured charge and reconciles uncertain provider outcomes.
Open practiceDesign a multi-tenant CI/CD control plane that safely orchestrates dependency-aware pipeline runs across regional data-plane worker fleets.
Open practiceDesign durable batched large-file upload, synchronous request outcomes, authorized download, content-addressed byte reuse, offline terminal notification, and reference-safe deletion.
Open practiceDesign a browser-based coding workspace that durably stores repositories around 100 GB, resumes quickly after idle, and safely places isolated workspaces on dedicated or shared execution hosts.
Open practiceDesign a highly available text-generation service that streams model responses, scales scarce inference capacity, recovers from failures, and exposes useful operational metrics.
Open practiceModel notification fanout across email, SMS, and Slack when each channel can have multiple bot integrations.
Open practiceDesign a global platform that turns microservice metrics into honest health dashboards and timely, deduplicated anomaly alerts.
Open practiceModel versioned three-card rules that classify, fold, compare, and log a round without coupling rule evolution to orchestration.
Open practiceDesign a global game store with publisher release ingestion, region-aware browse and search, retry-safe commerce, personal libraries, large build delivery, reviews, and bounded launch authorization.
Open practiceDesign a reusable platform that measures agent quality from online feedback and reproducible offline evaluations without coupling teams to one agent implementation.
Open practiceDesign matchmaking, authoritative game sessions, routing, and chess-clock timeout behavior for an online chess service that can grow from a new product.
Open practiceDesign a correct payment-recording and nightly reconciliation system for in-store merchants and their acquiring banks.
Open practiceDesign a Sora-like platform that durably schedules long-running video-generation jobs, survives infrastructure failures, and publishes complete video artifacts.
Open practiceDesign a demand-response control plane that detects overload, protects critical loads, requests voluntary reductions, and reconciles unreliable device evidence.
Open practiceDesign reliable offline device log collection, targeted capture requests, reconnect-storm ingestion, and late-corrected metrics.
Open practiceDesign a platform that ingests generating-unit telemetry and runs durable distributed analyses for plant operators.
Open practiceDesign a bounded peer-message protocol for GPU workers, with ordered receipt, retry behavior, restart detection, and overload control.
Open practiceDesign isolated organization messaging with ordered conversations, search, presence, read cursors, and offline delivery.
Open practiceDesign a distributed search service that solves crossword grids while preventing workers from exploring the same logical search state.
Open practiceDesign a two-region control plane that plans and applies versioned infrastructure changes safely across unreliable provider APIs.
Open practiceDebug a multi-rule Django rate limiter so sliding windows stay independent, atomic, bounded, and safe under concurrent requests.
Open practice03 · Evidence boundary
It means practicing transferable implementation, testing, and technical reasoning with public catalog assets FastPrep tags to OpenAI. It does not mean FastPrep has access to the company's assessments or any private interview bank.
Repeated public sightings and last-reported dates can help you prioritize practice, but they cannot predict the questions, format, or platform in a specific interview.
04 · Plain answers
This page owns technical-practice intent for OpenAI. Hiring activity, timelines, and market signals remain on the separate hiring-insights page.
Yes, when the public catalog supports it. This page currently links 21 system-design exercises, 2 low-level-design exercises, and 1 project-coding exercise tagged to OpenAI. Empty formats are omitted rather than padded with generic recommendations.
No. FastPrep is an independent interview-preparation product and is not affiliated with OpenAI. The page uses FastPrep's public practice catalog and does not claim official, private, leaked, or proprietary employer questions.
Stage labels come from FastPrep's public problem metadata. A problem can carry more than one reported stage, and hiring processes can change by role, level, location, and date. Treat the labels as preparation context, not a guarantee.
Start with the stage named in your invitation or recruiter message. If no stage is known, use the largest available set to build general problem-solving fluency, then rehearse explanation and testing separately.
No. Public catalog counts, stage tags, and last-reported dates can help prioritize practice, but they cannot predict a specific interview's questions, sequence, timing, or platform.
Your next stage, made concrete
Start with the stage named in your invitation, then use public evidence as context—not as a promise of what you will be asked.
Open the practice set