OpenAI Data Scientist Interview Questions

Preparing for OpenAI Data Scientist interview questions requires a blend of deep technical fluency, product-oriented thinking, and clear communication. OpenAI interviews are distinctive for their emphasis on real-world modeling and experimentation: expect deep dives into past projects, hands-on SQL and Python problem solving, machine learning theory and evaluation, and questions that probe your ability to design scalable data pipelines and reliable experiments. Interviewers evaluate your analytical rigor, statistical intuition, coding hygiene, and how you reason about tradeoffs and safety in AI applications. For strong interview preparation, prioritize polished explanations of your biggest projects, practice implementing and debugging models and SQL queries under time pressure, and rehearse structured behavioral stories that show impact, ownership, and collaboration. Simulate technical deep dives with peers, review experimental design and common ML failure modes, and be ready to discuss product metrics and deployment considerations. Finally, align your examples to OpenAI’s mission and be concise: clear thinking and high-leverage decisions matter as much as raw technical skill.

21 Questions 1 Company02.18.2026
Showing 20 results
Role
OpenAI logo
OpenAI
Hard
Data Scientist

Debug and fix a PyTorch Transformer training loop

Minimal Causal LM Debugging and Optimization You are given a tiny causal decoder-only language model implemented in PyTorch. It appears to "train" but...

Machine Learning
311
0
2112 people solved
Oct 13, 2025
OpenAI logo
OpenAI
Hard
Data Scientist

Design a free-month experiment

An online subscription product is considering a promotion that gives eligible new users their first month free instead of charging immediately. Design...

Analytics & Experimentation
55
0
398 people solved
Feb 3, 2026
OpenAI logo
OpenAI
Medium
Data Scientist Locked

Implement NumPy neural-network layers

This question evaluates competency in implementing neural-network layers and array algebra in NumPy, including matrix multiplication, broadcasting rul...

Machine Learning
43
0
353 people solved
Feb 18, 2026
OpenAI logo
OpenAI
Medium
Data ScientistSenior+

Debug and harden trial-assignment Python code

You are given the following simplified Python snippet used to assign users and trigger a 1‑month free trial: """ import random, datetime, requests def...

Data Manipulation (SQL/Python)
38
0
457 people solved
Oct 13, 2025
OpenAI logo
OpenAI
Hard
Data Scientist Locked

Assess free-month promotion impact

This question evaluates a data scientist's competency in experimental design, causal inference, metric definition and prioritization, bias identificat...

Analytics & Experimentation
15
0
218 people solved
Jan 22, 2026
OpenAI logo
OpenAI
Hard
Data Scientist

Write SQL for repeat churn

Write a SQL query to measure the performance of a free-month promotion experiment. Assume experiment_users already contains only users who were eligib...

Data Manipulation (SQL/Python)
36
0
345 people solved
Feb 3, 2026
OpenAI logo
OpenAI
Easy
Data Scientist

Compute signup rate and retention from raw logs

Scenario You are analyzing an A/B test for a marketing campaign offering a free 1-month trial. You are given raw “upstream” tables that resemble produ...

Data Manipulation (SQL/Python)
3
0
34 people solved
Oct 4, 2025
OpenAI logo
OpenAI
Hard
Data ScientistSenior+

Design and analyze a free-trial A/B test

A/B Test Design: 1‑Month Free Trial Impact on Paid Subscription Conversion You are evaluating whether offering a 1‑month free trial increases paid sub...

Analytics & Experimentation
31
0
232 people solved
Oct 13, 2025
OpenAI logo
OpenAI
Hard
Data Scientist Locked

Measure free-month promotion impact

This question evaluates causal inference and experimentation skills, including randomized design and estimand framing, metric and ROI attribution, han...

Analytics & Experimentation
15
0
135 people solved
Jan 15, 2026
OpenAI logo
OpenAI
Medium
Data Scientist

Write SQL to compute signup and retention lift

You are analyzing an A/B test for a marketing campaign that offers a free 1‑month trial. Assume all timestamps are in UTC. Tables experiment_assignmen...

Data Manipulation (SQL/Python)
15
0
131 people solved
Oct 8, 2025
OpenAI logo
OpenAI
Hard
Data Scientist Locked

Handle repeated churn in SQL

This question evaluates proficiency in time-based data manipulation and analytics, including handling repeated churn and resubscription, interval logi...

Data Manipulation (SQL/Python)
14
0
117 people solved
Jan 22, 2026
OpenAI logo
OpenAI
Medium
Data Scientist

How would you evaluate a free-trial A/B test?

You run an online marketing experiment to evaluate whether offering a free 1‑month trial increases growth. Experiment context - Eligible visitors are ...

Analytics & Experimentation
9
0
180 people solved
Oct 8, 2025
OpenAI logo
OpenAI
Medium
Data Scientist

Design Schema for Accurate Subscription State Tracking

subscription_events +----------+---------------------+-----------+-----------+ | user_id | event_ts | event_type| plan_type | +----------+...

Data Manipulation (SQL/Python)
137
0
414 people solved
Aug 4, 2025
OpenAI logo
OpenAI
Hard
Data Scientist Locked

Compute churn with re-subscriptions

This question evaluates proficiency in event-time data manipulation, temporal aggregation, and subscription-state logic for computing conversion and r...

Data Manipulation (SQL/Python)
11
0
99 people solved
Jan 15, 2026
OpenAI logo
OpenAI
Medium
Data Scientist

Analyze A/B Test Results for Subscription Conversion Rates

Analyze A/B Test Results for Subscription Conversion Rates An A/B test offers free users a limited-time trial of the paid plan to see whether it incre...

Analytics & Experimentation
121
1
303 people solved
Jul 12, 2025
OpenAI logo
OpenAI
Medium
Data ScientistSenior+

Write SQL for post-trial conversion cohorts

Using the schema below, write SQL to compute, for users first exposed between 2025‑06‑01 and 2025‑06‑30 (inclusive), the intent‑to‑treat paid conversi...

Data Manipulation (SQL/Python)
2
0
15 people solved
Oct 13, 2025
OpenAI logo
OpenAI
Medium
Data Scientist

Determine Metrics to Measure Free-Trial Impact on Subscriptions

Determine Metrics to Measure Free-Trial Impact on Subscriptions A/B Test: Free Trial Offer Impact on Subscription Behavior Scenario You are analyzing ...

Analytics & Experimentation
60
0
149 people solved
Aug 4, 2025
OpenAI logo
OpenAI
Easy
Data Scientist Locked

Evaluate a free-trial A/B test

This question evaluates skills in experimental design, causal inference and statistical analysis, metric definition and instrumentation, data-quality ...

Analytics & Experimentation
7
0
134 people solved
Oct 4, 2025
OpenAI logo
OpenAI
Medium
Data Scientist

Design Schema and Logic for Subscription Event Tracking

user_subscription_events +----------+-------------+---------------------+-----------+---------+ | user_id | event_type | event_time | plan_...

Data Manipulation (SQL/Python)
71
0
159 people solved
Jul 12, 2025
OpenAI logo
OpenAI
Medium
Data Scientist Locked

Design plant-infection algorithms

This question evaluates algorithm design and simulation skills for a data scientist role, focusing on modeling contagion spread on an m-by-n grid, eve...

Coding & Algorithms
5
0
46 people solved
Feb 18, 2026

Frequently Asked Questions

How difficult are OpenAI Data Scientist interviews?
OpenAI Data Scientist interviews are competitive and intellectually demanding. Expect a rigorous evaluation of statistical reasoning, machine learning intuition, coding ability in Python and SQL, and the ability to communicate complex results clearly. Difficulty varies by seniority: junior roles emphasize fundamental tooling and experimental design, while senior roles probe architecture, model scalability, and research judgment. Interviewers look not only for correct answers but for clear tradeoff analysis, thoughtful assumptions, and mission alignment. With focused practice on practical modeling, experiments, and behavioral stories, many candidates can perform strongly despite the high expectations.
What is the typical interview process and where do data science topics appear?
The typical process begins with a resume screen and recruiter or hiring manager conversation, followed by skills assessments or take-home tasks, then a set of final interviews with cross functional teammates. Data science topics appear throughout: coding and SQL tests evaluate data manipulation and reproducibility, technical deep dives probe past projects and modeling choices, dedicated ML or statistics interviews test experimental design and causal reasoning, and product or analytics sessions assess metric design and impact. There is also a behavioral component that examines collaboration, ownership, and alignment with safety and ethical considerations.
How should I structure my interview preparation timeline for OpenAI Data Scientist roles?
Structure preparation across four to eight weeks with focused milestones. Start by polishing your resume and curating two to three projects that showcase impact and technical depth. Spend early weeks reinforcing core skills: SQL query fluency, Python data manipulation, and key statistical concepts. Midway, practice modeling, experimental design, and end-to-end case studies, including clear evaluation and deployment considerations. In the final weeks, simulate technical deep dives and mock interviews, refine behavioral STAR stories, and rehearse concise explanations of tradeoffs. Leave time for rest, logistics, and company research so you enter interviews focused and confident.
What key subtopics should I master for OpenAI Data Scientist interviews?
Master SQL and Python for data extraction and transformation, and build strong intuition for statistical inference, hypothesis testing, confidence intervals, and power. Be fluent in common machine learning algorithms, evaluation metrics, regularization, and overfitting mitigation, as well as feature engineering and model validation. Understand experimental design and causal reasoning for A/B tests at scale, and be ready to discuss data pipelines, monitoring, and practical deployment tradeoffs. Product analytics skills such as metric design, funnel analysis, and root cause diagnosis are often tested alongside communication and reproducibility practices.
What standout tips and common pitfalls should I know for these interviews?
Standout tips include telling concise impact-driven stories, quantifying outcomes, and preparing a deep dive for each highlighted project that covers data, assumptions, alternatives, and limitations. During technical problems, explicitly state assumptions, check edge cases, and discuss computational costs and reliability. Common pitfalls are vague metrics without context, ignoring reproducibility or experiment power, failing to justify model choices, and weak communication of uncertainty. Demonstrating mission and safety awareness, and asking clarifying questions, differentiates strong candidates from those who only solve isolated technical problems.

Explore more OpenAI Data Scientist interview questions

Real questions from candidate reports, grouped by topic, role and company.

Other roles at OpenAI
Data Scientist questions at other companies
Browse all