Google Technical Phone Interview: What to Expect

The Google technical phone interview is a 45 minute live coding session with a Google engineer. You write code in a shared online document while the interviewer watches and asks questions.

Telephonic interview is the same thing under another name. It means an interview held over a phone or video call instead of in an office.

The part that surprises people is the editor. Candidates report a plain shared document with no autocomplete, no syntax highlighting, and usually no way to run the code.

How the 45 minutes are spent

The shape is consistent, so you can plan around it.

Losing ten minutes at the start is a common failure. Keep your own introduction under two minutes.

What gets asked

The topics are standard data structures and algorithms. There is no trivia about Google products.

• Arrays, strings and hash maps.
• Trees and graphs, with breadth first and depth first traversal.
• Sorting and binary search, usually as one step inside a bigger problem.
• Recursion, and sometimes dynamic programming.
• Complexity analysis for whatever you wrote.

System design appears in the phone screen only for senior roles. For most candidates it starts at the onsite.

Writing code with no help from the editor

Because the document does not run your code, three habits matter more than usual.

• Say the approach before you type. Get agreement on the plan, so you do not write 30 lines in the wrong direction.
• Write full names and full syntax. No autocomplete means small errors stay in the text where the interviewer sees them.
• Read your own code out loud at the end. Walk through one small input by hand and fix what breaks.

Practise this way too. Solve three problems a week in a plain text editor with no run button.

What separates a pass from a fail

An interviewer writes feedback immediately afterwards. They need to describe how you thought, not only what you produced.

• Passing looks like: clarifying questions first, a stated approach, working code, correct complexity, then a clean answer to one follow up.
• Failing looks like: long silence, coding before agreeing an approach, a brute force solution left unimproved, or code that never gets finished.

A solution that is correct but slow is not automatically a fail. Not noticing that it is slow usually is.

After the phone screen

Your recruiter delivers the result, not the interviewer. Candidates report one to two weeks, and longer during busy periods.

Some candidates are asked for a second phone screen. That is common and it is not a bad sign on its own.

A pass leads to the onsite stage of four or five interviews. The full timeline is in how long the Google interview process takes.

How this differs from the online test

The online test comes earlier and has no human in it. It is two problems in 60 to 90 minutes, graded automatically.

The phone screen is graded by a person who cares how you got there. See what the Google Online Assessment is for that earlier stage.

How to Prepare

• Practise in a plain document. No autocomplete, no run button, one problem in 35 minutes.
• Learn the patterns, not a problem list. Grokking the Coding Interview groups questions by the shape of the solution.
• Repair weak data structures first. Grokking Data Structures for Coding Interviews covers trees, graphs and hash maps.
• Rehearse talking while coding. Book mock interviews or record yourself and listen back once.
• Choose your language in advance. Use the one you write fastest. See which language is best for a Google coding interview.
• Know what comes next. Read what to expect in a Google first interview and the top coding interview questions for Google.