What Really Happens in a Google Engineer Interview? A Firsthand Six‑Round Journey

Personal Background

The author holds a 985 undergraduate degree and a top‑2 master's degree, with over four years of experience as a backend development team lead at DJI.

Interview Process

Recruiter Prescreen

Phone Interview (1–2 sessions)

Onsite Interview (4–5 sessions, feedback in one week)

Hiring Committee Review

Offer Review

Offer Delivery

In total the author completed 1 phone round and 5 onsite rounds, 7 rounds including the HR prescreen.

HR Interview

The first round is a recruiter prescreen consisting of basic computer‑science fill‑in‑the‑blank and multiple‑choice questions such as quick‑sort complexity or stability of selection sort; answers are not required to be explained in detail.

Phone Interview

Conducted via a shared Google Doc, requiring a stable network. The author faced a binary‑tree traversal problem embedded in a business scenario, wrote code, and answered follow‑up questions on edge cases and optimizations.

Onsite Interview

The onsite day comprised five one‑hour sessions, often scheduled in two half‑days. Topics covered included coding, algorithms (e.g., Dijkstra, A*), sorting, data structures, mathematics, graph traversal, recursion, and system design.

Coding: implement a problem in any familiar language.

Algorithms: sorting, searching, divide‑and‑conquer, dynamic programming, greedy, recursion, plus graph algorithms like Dijkstra and A*.

Sorting: quick‑sort, merge‑sort, heap‑sort, insertion, radix, etc.

Data structures: arrays, linked lists, heaps, stacks, hash tables, trees.

Mathematics: discrete and combinatorial concepts.

Graph: representations, BFS/DFS.

Recursion: conversion between recursive and iterative forms.

Other: system design and operating‑system concepts.

A sample onsite question resembled a LeetCode two‑dimensional matrix shortest‑path problem solvable with dynamic programming, and another focused on binary‑tree traversal without requiring recursive code.

The author also faced a system‑design question about a knowledge‑graph, requiring a whiteboard design and iterative improvement.

Lunch

During the onsite day, a Google engineer joined for lunch, providing informal insight into life at Google.

English Interview

Two of the onsite sessions were conducted in English; preparation should include practicing technical vocabulary and mock interviews.

Additional Resources

The author offers to share the "Google Engineer Interview Guide.pdf" with interested readers via a WeChat contact or email.