Anthropic Interview Questions
Reconstructed from 580 verified candidate reports across 51 questions. Nov 2024 – May 2026.
This page is a live view of every Anthropic interview question AceOffer has indexed — pulled from real candidate reports, not invented from job descriptions or one founder’s memory. Every question shows how many times it’s been reported and when it was last seen. The catalog gets a refresh pass every month.
Key facts
- •51 distinct Anthropic interview questions indexed
- •580 candidate reports across the catalog
- •Most reported: Web Crawler — 60× (last seen July 2026)
- •Reports span Nov 2024 – May 2026
- •Refreshed monthly · last updated September 2026
Browse Anthropic interviews by topic
Deep-dive guides
The Anthropic loop, from candidate reports
Anthropic's loop is recruiter screen → CodeSignal-style 90-minute Python coding assessment → 1–2 phone screens → a 5-round virtual onsite. The behavioral round at Anthropic is unusually deep and weighted: the interviewer probes AI safety alignment with specific hypothetical scenarios, and candidates report being asked 'why Anthropic over OpenAI' with the expectation of a substantive answer that goes beyond mission slogans. The Web Crawler phone screen has shown up in 49 reports — it's effectively a filter. For ML / Research Engineer roles, the MLE round combines an inference-API system design with deep questions on tokenizer implementation, image-processing pipelines, and Python-from-scratch implementations.
What does Anthropic ask in each interview round?
Anthropic interviews span 6 distinct round types, broken down below. Counts reflect distinct questions per round, not number of times asked. Frequencies on individual question cards show how many candidates reported getting that specific question.
Two-way conversations. Anthropic in particular probes AI safety alignment hard; OpenAI probes mission-fit and shipping velocity.
60 minute design rounds. Interviewers push hard on the specific dimension their team cares about (storage at scale, real-time fan-out, multi-tenancy).
Take-home or proctored 90-minute online assessment before the loop. Used as a filter — not weighted in the final decision once you're in the onsite.
Implement forward + backward from scratch (NumPy), debug a planted-bug transformer, or design an ML system. Math + code + system thinking.
60–75 minute live coding rounds. Multiple sub-problems progressing in difficulty. Test harness usually provided.
60–90 minute coding or system design over CoderPad or similar. Pass bar is correctness + clean communication; brilliance isn't required.
Which Anthropic interview questions come up most?
These are the Anthropicquestions reported most across the loops we’ve indexed, sorted by candidate-report frequency.
| Question | Round | Reported | Last seen |
|---|---|---|---|
| Web Crawler | Phone Screen | 60× | July 2026 |
| File Deduplication | Coding | 53× | September 2026 |
| Culture Fit / Behavioral Questions | Behavioral | 42× | August 2026 |
| Profiling / Stack Trace Analysis | Coding | 41× | August 2026 |
| Inference API System Design | System Design | 40× | August 2026 |
| AI Safety Culture Fit | Behavioral | 29× | August 2026 |
| Why Anthropic? | Behavioral | 29× | August 2026 |
| Image Processing Pipeline | Coding | 26× | August 2026 |
| Most Impactful Project / HM Behavioral | Behavioral | 24× | August 2026 |
| Project Deep Dive / Technical Presentation | Behavioral | 21× | August 2026 |
The full index is below, or browse the Anthropic catalog →
Every Anthropicinterview question we’ve indexed
All 51, grouped by round and sorted by how often candidates reported them. Each links to the question, its reported follow-up count, and when it was last seen.
Behavioral (12)
- Culture Fit / Behavioral Questions — reported 42×, last seen August 2026
- AI Safety Culture Fit — reported 29×, last seen August 2026
- Why Anthropic? — reported 29×, last seen August 2026
- Most Impactful Project / HM Behavioral — reported 24×, last seen August 2026
- Project Deep Dive / Technical Presentation — reported 21×, last seen August 2026
- Project Feasibility / Failure BQ — reported 9×, last seen April 2026
- Career Plan / Work Preferences — reported 4×, last seen June 2026
- Thoughts on Anthropic as a Company / HM Discussion — reported 2×, last seen September 2025
- Most Challenging Project (Recruiter Chat) — reported 2×, last seen March 2026
- Open-Source AI Safety / Community Benefit Discussion — reported 2×, last seen March 2026
- Open-ended Research Question (Take-home) — reported 1×, last seen June 2026
- Dataset Analysis with Cloud Capacity Management — reported 1×, last seen June 2026
System Design (11)
- Inference API System Design — reported 40×, last seen August 2026
- ML Model Distribution / Deployment System Design — reported 16×, last seen August 2026
- Prompt Playground System Design — reported 15×, last seen August 2026
- Batch Inference System Design — reported 12×, last seen August 2026
- GPU Cluster / Inference Infrastructure System Design — reported 7×, last seen August 2026
- Chat System Design (1-on-1) — reported 7×, last seen August 2026
- GPU Allocation for Mixed Large/Small Model Inference — reported 3×, last seen August 2026
- Roofline Model Analysis — reported 3×, last seen December 2025
- System Design Doc Review — reported 3×, last seen April 2026
- Stream Large File to Many Machines — reported 2×, last seen June 2026
- Amusement Park / Sharing System Product Design — reported 1×, last seen April 2026
OA (9)
- Banking System (OA) — reported 17×, last seen July 2026
- In-Memory Database — reported 16×, last seen July 2026
- File Systems OA (Multi-Part) — reported 8×, last seen May 2026
- Recipe Manager — reported 6×, last seen April 2026
- Task Management System — reported 5×, last seen August 2026
- VLIW / TPU / Kernel Optimization Assignment — reported 4×, last seen December 2025
- Cloud File Storage System — reported 3×, last seen July 2026
- Debugging Exercise (OA Part ii) — reported 1×, last seen June 2026
- Step-by-step Implementation (OA Part i) — reported 1×, last seen June 2026
MLE (9)
- Debug GRPO / RL Training Code — reported 4×, last seen March 2026
- NumPy Debugging — reported 4×, last seen May 2026
- Neural Network Forward and Backward Pass Implementation — reported 2×, last seen July 2025
- Data Batcher with Weighted Sampling — reported 2×, last seen April 2026
- LLM-Based Binary Classifier Design — reported 1×, last seen July 2025
- Attention Algorithm Implementation in PyTorch — reported 1×, last seen July 2025
- Sample-Aspect Double Descent Experiment Design — reported 1×, last seen April 2026
- Multi-layer Pattern Performance with Memory Constraints — reported 1×, last seen September 2025
- A100 Matrix Multiplication Performance Modeling — reported 1×, last seen September 2025
Coding (6)
- File Deduplication — reported 53×, last seen September 2026
- Profiling / Stack Trace Analysis — reported 41×, last seen August 2026
- Image Processing Pipeline — reported 26×, last seen August 2026
- LRU Cache — reported 12×, last seen July 2026
- Distributed Mode/Median — reported 12×, last seen July 2026
- Bootloader with Loop Detection — reported 3×, last seen July 2026
Phone Screen (4)
- Web Crawler — reported 60×, last seen July 2026
- Tokenizer Implementation — reported 14×, last seen July 2026
- Claude Agent Loop with Multi-Step Tool Calling — reported 3×, last seen August 2026
- Consecutive Event / Sample Detection — reported 3×, last seen December 2025
Read two Anthropic questions free
Full problem statements, candidate-reported follow-ups, and walkthroughs. No signup needed.
Crawl every page within the same hostname using a provided link helper. Start single-threaded, then make it concurrent. The most-reported Anthropic question by a wide margin.
Design a prompt playground — stateless conversation turns, share-conversation feature, very large prompts. The interviewer probes UX, frontend state, and the share mechanism in depth.
Live-debug a buggy GRPO training script. Three planted bugs — softmax before multinomial, epsilon-less std, and the importance-sampling ratio formula — then RL-theory follow-ups on PPO clipping and mini-epoch policy drift. The Anthropic Research / MLE signature debug round.
- •On the behavioral round: come with one specific Anthropic alignment paper or recent decision (RSP, Constitutional AI, the deprecation policy) and connect it back to your own work — generic safety enthusiasm gets flagged
- •On Web Crawler: progressive complexity wins — solve single-threaded clearly first, then propose the concurrent extension with the interviewer's blessing. Don't dive into concurrency immediately
- •On Inference API system design: distinguish the routing layer (cheap, stateless) from the model serving layer (expensive, GPU-pinned) early, then build from there
- •For the MLE round: have NumPy implementations of softmax + cross-entropy and backprop through MLP cold — the interviewer expects you to derive without looking things up
- •Quote your work back as 'I made this technical decision because of X tradeoff' — not 'I worked on Y' — Anthropic's deep-dive round is grading reasoning, not titles
- •Treating the AI safety culture round as a soft round and giving a corporate-policy answer — gets flagged as 'low alignment signal' and reported as a primary loss reason
- •On Web Crawler: jumping to a concurrent solution without verifying the single-threaded version against the test cases first
- •Skipping the URL normalization step on Web Crawler (fragments, query params, trailing slashes) — multiple candidates lost the round on this single edge case
- •On Inference API: conflating the model-routing problem with the model-serving problem; not distinguishing latency-sensitive (real-time) from throughput-optimized (batch) workloads
- •On the project deep-dive: presenting WHAT you built without articulating the alternatives you considered and why you rejected them
Get the full Anthropic catalog
Every question. Every candidate-reported follow-up. The mistakes that sink people, and what passers do instead. Monthly refresh.