OpenAI Coding & Algorithms Interview Questions

Preparing for OpenAI Coding & Algorithms interview questions requires recognizing that OpenAI blends classic algorithmic rigor with product- and safety-oriented thinking. Interviews test algorithmic problem solving, data structures, time/space trade-offs, clean testable code, and the ability to reason about scaling, failure modes, and abuse vectors for real systems. Expect a multi-stage process—recruiter screen, one or two technical screens (pair coding or timed coding), and a final loop of 4–6 interviews covering coding, system design, deep-dives, and behavioral questions—lasting a few hours over one or two days. For interview preparation, practice medium-to-hard coding problems, timed pair-coding, system design scenarios relevant to model serving and data pipelines, and prepare concise STAR examples that highlight ownership and collaboration. Read OpenAI’s public materials and be ready to discuss trade-offs, testing, and safety considerations. Emphasize clear communication, test coverage, and justifying design choices; interviewers value well-reasoned, production-minded answers over trick solutions. Bring specific examples of shipping code and measurable impact.

90 Questions 1 Company08.01.2026
Showing 20 results
Role
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OpenAI
Hard
Software Engineer Locked

Compute Infection Time in a Grid

This question evaluates competence in grid-based graph traversal and simulation of propagation dynamics, focusing on state management, time-step model...

Coding & Algorithms
19
1
183 people solved
Apr 7, 2026
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OpenAI
Medium
Software Engineer

Implement a memory allocator with malloc/free

Problem You are implementing a simplified memory allocator over a contiguous memory region. Initialize the allocator with a fixed total size: - alloca...

Coding & Algorithms
19
0
201 people solved
Jan 9, 2026
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OpenAI
Medium
Machine Learning Engineer Locked

Simulate Plant Infection Spread

This question evaluates graph traversal and grid-based simulation skills, including modeling a 2D grid as a graph, propagation dynamics with obstacles...

Coding & Algorithms
6
0
75 people solved
Apr 3, 2026
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OpenAI
Medium
Software Engineer

Implement node messaging and path discovery

You have a network where each node knows only its parent and its children and can send messages to its parent and children. 1) Implement a sendMessage...

Coding & Algorithms
43
0
381 people solved
Jul 27, 2025
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OpenAI
Hard
Software Engineer

Implement an in-memory SQL-like table

Problem Implement a simple in-memory database for one table. All values are strings. Each row is identified by a rowKey (string). Each row contains co...

Coding & Algorithms
64
0
1069 people solved
Dec 15, 2025
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OpenAI
Medium
Software Engineer

Implement map serialization and deserialization

You are given an in-memory map (dictionary) from strings to strings. Implement two functions: - string serialize(map<string, string> m) - map<string, ...

Coding & Algorithms
78
0
616 people solved
Dec 1, 2025
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OpenAI
Medium
Software Engineer

Implement an expiring GPU-credit manager

Implement an expiring GPU-credit manager for a cloud provider. Each user receives credit grants with an amount and an expiration timestamp. Support: (...

Coding & Algorithms
54
0
480 people solved
Sep 6, 2025
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OpenAI
Medium
Machine Learning Engineer Locked

Infer Generic Return Types

This question evaluates understanding of type systems, generic unification, recursive data structures, substitution mechanics, and robust error handli...

Coding & Algorithms
13
0
108 people solved
Mar 9, 2026
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OpenAI
Medium
Software Engineer

Count Nodes Using Asynchronous Messages

You are given the identifier of a root node in a distributed network. Each node represents a separate machine. A node cannot directly inspect another ...

Coding & Algorithms
3
0
25 people solved
Mar 4, 2026
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OpenAI
Medium
Software Engineer Locked

Rebalance shard ranges under overlap limit

This question evaluates skills in interval and range management, constraint enforcement, and algorithmic problem solving related to overlapping intege...

Coding & Algorithms
40
0
288 people solved
Mar 1, 2026
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OpenAI
Hard
Software Engineer Locked

Implement follow graph with snapshots

This question evaluates a candidate's ability to design efficient persistent data structures and versioned state management for time-travel queries in...

Coding & Algorithms
27
1
205 people solved
Mar 1, 2026
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OpenAI
Medium
Software Engineer

Manage GPU Credits with Expiration

Question Implement a GPU credit manager supporting out-of-order operations: API add_credit(id, amount, timestamp, expiration) // adds ‘amount’ credit...

Coding & Algorithms
38
0
400 people solved
Aug 4, 2025
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OpenAI
Medium
Software Engineer

Implement persistent key-value store

Question Design and implement an in-memory key-value store supporting set(key, value), get(key), shutdown() that flushes all data as bytes to a medium...

Coding & Algorithms
22
0
299 people solved
Aug 4, 2025
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OpenAI
Medium
Software Engineer Locked

Implement Time-Aware GPU Credit Ledger

This question evaluates the ability to design efficient data structures and algorithms for time-aware resource accounting, including handling overlapp...

Coding & Algorithms
5
0
62 people solved
Feb 23, 2026
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OpenAI
Easy
Software Engineer Locked

Simulate a Turn-Based Two-Player Game

This question evaluates API design, state management, move validation, board representation, and correctness guarantees for a turn-based game simulato...

Coding & Algorithms
11
0
78 people solved
Feb 13, 2026
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OpenAI
Medium
Machine Learning Engineer Locked

Find the First Working Version

This question evaluates understanding of search algorithms, version normalization, and monotonic predicates, along with competency in parsing and orde...

Coding & Algorithms
3
0
20 people solved
Feb 1, 2026
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OpenAI
Medium
Software Engineer Locked

Implement Three Research Coding Tasks

This multi-part question evaluates skills in differentiable linear algebra and automatic differentiation safety, memory- and buffer-aware numerical im...

Coding & Algorithms
5
0
45 people solved
Jan 13, 2026
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OpenAI
Medium
Software Engineer Locked

Compute infection spread time

This question evaluates understanding of grid-based graph traversal and propagation dynamics, testing competencies in breadth-first search concepts, s...

Coding & Algorithms
9
0
126 people solved
Jan 9, 2026
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OpenAI
Hard
Software Engineer Locked

Refactor a chat message processing function

This question evaluates a candidate's ability to refactor and implement clear, maintainable message-processing logic—covering code organization, comma...

Coding & Algorithms
18
0
165 people solved
Jan 2, 2026
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OpenAI
Medium
Software Engineer

Implement in-memory KV store with serialization

Implement an in-memory key-value store in Python that supports setting and retrieving values and can serialize and deserialize the entire store. Defin...

Coding & Algorithms
40
0
361 people solved
Aug 8, 2025

Frequently Asked Questions

How difficult are OpenAI Coding & Algorithms interview questions?
OpenAI Coding & Algorithms questions are often described as medium-to-hard in difficulty and emphasize practical engineering judgment as much as algorithmic correctness. Expect problems that require clean, testable code, attention to edge cases, and a clear discussion of time and space complexity rather than obscure puzzle tricks. Interviewers frequently push candidates to adapt solutions for production constraints, performance trade-offs, and maintainability, so preparation should cover both problem solving and engineering reasoning.
What does the typical OpenAI interview process look like, and where do Coding & Algorithms questions appear?
The usual process starts with a recruiter screen, followed by one or more technical assessments that vary by role, and culminates in final interviews that include coding, system design, and behavioral rounds. Coding and algorithms work commonly appears in the technical phone screen and in one or more live coding sessions during the final loop; some teams also use take-home exercises or pair-programming assessments. Interviewers evaluate correctness, performance, readability, and testing practices alongside communication and collaboration.
What is a sensible prep timeline to get ready for OpenAI Coding & Algorithms interviews?
A sensible timeline depends on your starting point, but many candidates follow a six- to eight-week focused plan if they have solid foundations, while those needing refreshes may take three months. Early weeks should reinforce core data structures and algorithm patterns and include timed practice in a shared editor; middle weeks should combine medium-to-hard problems with mock interviews and system-oriented algorithm questions; final weeks should emphasize code quality, testing, and rehearsing clear explanations. Recruiters often move candidates through stages in a few weeks, so align your prep with expected scheduling.
Which subtopics within Coding & Algorithms should I prioritize for OpenAI interviews?
Prioritize robust fundamentals like arrays and strings, hash maps and sets, tree and graph traversals, dynamic programming, and complexity analysis, while also practicing problems that bridge algorithms with real-world engineering such as caching, streaming, or rate-limiting logic. Equally important are writing readable, well-tested code and explaining trade-offs as you optimize. For many roles you should also be comfortable reasoning about scalability, correctness under edge cases, and how algorithmic choices affect production behavior. Practice problems that prompt you to move from a correct solution to a production-ready design.
What standout tips and common pitfalls should I know when preparing for OpenAI Coding & Algorithms interviews?
Standout tips include practicing in the same environment used by interviews, narrating your thought process clearly, writing concise tests and handling edge cases, and demonstrating trade-off reasoning when you optimize. Avoid common pitfalls like rushing to code without a plan, ignoring input validation and null cases, overfitting to toy examples, or sacrificing readability for micro-optimizations. Interviewers value pragmatic, maintainable solutions and strong communication, so balance algorithmic correctness with engineering hygiene and be ready to iterate on feedback during the session.

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