Meta Interview Questions — Page 154

Meta·Data Scientist·Technical Phone Screen

Jun 2026

Got a product experimentation question for a DS role at Meta, centered on an ad tool feature. The whole thing was a single meaty case study and they really wanted to see you sweat the details on measurement design, not just rattle off metrics.

Meta is building a feature that notifies advertisers when their Ads Pixel appears misconfigured or is sending low-quality signals, along with a suggested fix. How would you design an experiment to evaluate whether this feature is actually beneficial, and walk through everything from the hypothesis and randomization unit to metrics and how you'd handle tricky interpretation issues like improved tracking inflating conversion numbers?

“This question is a beast.”

View Post

Meta·Data Scientist·Technical Phone Screen

Jun 2026

Algorithmic screen for a Data Scientist role on Meta's VR/AR side, two back-to-back greedy problems with a clear theme once you spotted it. Nothing too wild but the second problem tripped me up longer than I'd like to admit.

Given an array of frame sizes and a bandwidth limit, split the array into the minimum number of contiguous segments such that the sum of each segment does not exceed the bandwidth limit. Return that minimum count.
Given n circles on a 1D line each represented by a center and radius, find the minimum number of arrows shot at a horizontal position p that would burst every circle, where a circle is burst if center minus radius is less than or equal to p and p is less than or equal to center plus radius.

“Greedy running sum, pretty mechanical once you see it.”

View Post

Meta·Software Engineer·Onsite - Coding / Algorithms

Jun 2026

Virtual onsite coding round at Meta for a software engineer role. One question, object-oriented design flavor, asked me to implement a card deck from scratch.

Design and implement a standard card deck in an object-oriented way, including relevant data structures and operations.

“Seemed straightforward at first and I kind of rushed into coding without thinking through the class hierarchy.”

View Post

Meta·Machine Learning Engineer·Onsite - Behavioral / Leadership

Jun 2026

Behavioral round for an MLE role at Meta, two questions, pretty standard stuff. Went in expecting something trickier and came out feeling like I probably over-prepared the technical side and under-prepared the people stories.

Tell me about a time you had a conflict with a peer or a cross-functional partner. How did you handle it and what happened?
Walk me through a challenging project you worked on. What made it hard, what was your role, and how did you push through the challenges?

“I had a decent story ready but fumbled the ending.”

View Post

Meta·Software Engineer·Onsite - Coding / Algorithms

Jun 2026

Meta SWE coding round focused on string-based expression evaluation, basically the classic calculator problems from LeetCode. The Meta variant adds some twists that can catch you off guard if you only prepped the vanilla version.

Implement a basic calculator that evaluates an arithmetic expression string containing +, -, *, / and parentheses, returning an integer result with division truncated toward zero.
Extend your calculator solution to handle additional operator precedence rules, such as an exponentiation operator, or custom operator definitions introduced by the interviewer.

“The multi-digit number part is where I almost slipped up.”

View Post

Meta·Machine Learning Engineer·Technical Phone Screen

Jun 2026

Coding screen for an ML Engineer role at Meta. One algorithmic question, substring matching, but they pushed past the naive solution pretty fast so be ready to actually discuss complexity and tradeoffs.

Given a list of strings, write a function that returns any string in the list which contains at least one other string from the same list as a contiguous substring. Return an empty string if none exist. Then walk through the time and space complexity, and describe two or three approaches that beat brute-force pairwise comparison.

“The basic O(n^2 * m) nested loop solution took maybe five minutes to write but they immediately asked me to do better.”

View Post

Meta·Software Engineer·Onsite - Behavioral / Leadership

Jun 2026

Meta staff-level behavioral loop focused on org-wide impact, cross-functional influence, and leadership dynamics. Four questions, all the classics, but the bar felt noticeably higher than a typical senior loop.

Tell me about a time you set technical direction for a team or organization.
Describe a situation where you disagreed with a leadership decision.
Walk me through a significant failure.
Tell me about a time you mentored or helped grow someone on your team.

“This one is where the level really shows.”

View Post

Meta·Data Scientist·Technical Phone Screen

Jun 2026

Meta DS interview with a meaty product case around estimating revenue potential for a new Shopping tab. Single question but it had like five sub-parts, so the whole session was basically one long back-and-forth working through the math and methodology.

Your team is evaluating a new Shopping tab in a social photo app. Organic posts and in-app search are the only channels in scope. Using available data (product page views, add-to-carts, purchases, average order value, and organic impression counts), estimate the monthly revenue potential if the tab launches to 100% of users. Walk through your full conversion funnel and the algebra behind it, explain how you'd get unbiased CTR and product page view rates from existing organic entry points, describe how you'd adjust for cannibalization of purchases that would have happened anyway through other surfaces, explain how you'd scale experiment results to the full user population while accounting for user heterogeneity, and finish with a sensitivity analysis on your key assumptions.

“This was a lot.”

View Post

Meta·Software Engineer·Technical Phone Screen

Jun 2026

Meta SWE coding round, just the one algorithmic problem about consecutive sequences. Pretty standard for them but the O(n) constraint is where people trip up.

Given an unsorted array of integers, return the length of the longest consecutive elements sequence. Your solution must run in O(n) time.

“The naive sort-based solution is O(n log n) and I kept second-guessing whether they'd accept it.”

View Post

Meta·Data Scientist·Technical Phone Screen

Jun 2026

SQL-heavy technical screen for a DS role at Meta. Two problems back to back, both ad-related, which makes sense given the business. The second one had a subtle FX join that I almost botched.

Given tables for ads, impressions, and conversions, write SQL to compare click-through rate during peak hours (6pm to 10pm UTC) versus all other hours, for active ads over the last 30 complete days. Return one row per time bucket with impression count, click count, and CTR.
Given ad revenue data by country and currency, plus an FX rates table, write SQL to calculate US-only revenue and global revenue in USD for each day in January 2024.

“The peak/non-peak bucketing is the core of this one.”

View Post