What Is the Google Online Assessment?

The Google Online Assessment is a timed coding test you take alone, before any live interview. It is usually two problems in 60 to 90 minutes. Google sends it mostly to intern and new graduate candidates.

For university hiring the same test is often called the Google Online Challenge, or GOC. The format is the same.

Experienced candidates usually skip it. They go straight from the recruiter screen to a phone screen with an engineer.

The test runs on HackerRank or on Google's own coding platform. The invitation email names the platform and the deadline, which is normally a few days.

What the test contains

The topics that come up

Questions stay inside standard data structures and algorithms. There is no system design and no trivia about Google products.

• Arrays, strings, and hash maps. The most common starting point.
• Trees and graphs. Breadth first and depth first traversal appear often.
• Sorting and binary search. Usually as one step inside a larger problem.
• Greedy choices and dynamic programming. Less common, and usually the harder of the two problems.

The problems are rarely obscure. The difficulty comes from time pressure, careful reading, and edge cases.

The part most candidates miss

You are given no sample test cases. Your code is scored against hidden tests after you submit.

That changes how you should work. Write two or three of your own test cases before you submit, including an empty input and the largest input the limits allow.

Check the stated input size. A limit near one million rules out a solution that compares every pair.

How it is scored and what happens next

Scoring is automatic. Correctness against the hidden tests matters most, and running inside the time limit matters next.

Google does not publish a passing score, and it does not send you your result. You learn the outcome from what happens next.

A pass brings an invitation to a phone screen with an engineer. Candidates report a wait of one to three weeks. Many candidates receive no rejection email at all.

Who gets sent the assessment

Not every applicant receives one. The pattern candidates report is consistent.

• Intern and new graduate applicants. Almost always, and often in large batches during campus hiring season.
• Applicants with one to three years of experience. Sometimes, depending on the team and the country.
• Senior applicants and referrals. Rarely, because a recruiter screen and a phone screen replace it.

If you were referred, ask your referrer what the team does. Some teams skip the test for every referral.

If you do not pass

Google does not tell you that you failed. The process simply stops.

There is a cooldown before you can apply again, and candidates report six months to a year. The recruiter who sent the test can confirm the date for your case.

A second attempt is normal and is not held against you. Many engineers at Google applied more than once.

How to Prepare

• Practise by pattern, not by problem count. The same shapes repeat, so learning the patterns is faster than grinding a long list. Grokking the Coding Interview is built around them.
• Time yourself properly. Sit two unseen problems in one 90 minute block, with no hints and no breaks.
• Practise writing your own tests. Solve in a plain editor with no sample cases given, since that matches the real test.
• Pick your language before test day. Use the one you write fastest, not the one you think looks best. See which language is best for a Google coding interview.
• Fix your data structure gaps first. If trees or graphs are slow for you, start with Grokking Data Structures for Coding Interviews.
• Know what comes after. Read what to expect in a Google coding interview, how hard the Google coding challenge is, and how long the Google interview process takes.