Amazon Online Assessment Guide: Format, Question Types, and How to Pass

The Amazon online assessment (OA) is a timed, unproctored test that Amazon sends after your application passes its first screening. It has two coding questions plus one or two behavioral sections. You must pass every section to be invited to the interviews.

Amazon receives far more applications than its engineers can interview. The OA reduces that number before any engineer spends an hour with you. Unproctored means no person watches you take it, and each section is judged on its own.

This guide describes the three versions of the OA and the coding question types. It then gives a time plan for the coding section and advice for the behavioral sections. It ends with what happens after you pass.

What the Amazon online assessment is

An online assessment is a test you take in a browser, on your own schedule, before any interview. Amazon emails the invitation once your application passes screening. You have seven days from that email to complete the test.

Amazon says it tells candidates within about two days whether they are invited to interviews. No Amazon-specific knowledge is needed. A practice test with two sample questions is available, and it does not affect your result.

The coding section runs on HackerRank, a browser-based coding platform that compiles and runs your code.

The details below come from Amazon's own preparation pages, as of this writing. Formats change. The invitation email is the final word: if it lists different sections or times, follow the email.

The three OA versions

Amazon sends a different OA depending on the role. The three common versions are for full-time new graduates, interns, and experienced engineers at the SDE II level. SDE is Amazon's title for a software development engineer, and SDE II is the level after entry.

The new grad version is the longest because it includes the Work Simulation. The intern version has no Work Simulation. The SDE II version gives 20 more minutes for coding and adds a short system design section.

Some candidates for experienced roles report a text box after each coding question. It asks them to explain their approach. Write two or three plain sentences there: the approach you used, its time cost, and one unusual input you handled.

The rules during the coding section

Amazon requires syntactically correct code. Pseudo code, which is a plain-language description of an algorithm that does not compile, is not accepted.

Amazon's page says you may use publicly accessible online resources during the coding section. You must not copy and paste code, and you must not use print screen to take screenshots. The work has to be your own.

Candidates report that both coding questions must compile before you can continue to the next section. Compiling means the platform can turn your code into a runnable program without syntax errors.

A half-written solution with a missing bracket can stop you from continuing. Always leave your code in a state that runs.

Coding question types

Candidates report that the two questions are usually easy to medium in difficulty. They use a small set of well-known patterns. A pattern is a reusable way of solving many similar questions.

A hash map is a table that stores values under keys. It finds any key in constant time, which means the same time however many keys it has. A heap is a tree that returns its smallest or largest item in logarithmic time, which grows very slowly as the heap grows.

Breadth-first search (BFS) visits a graph level by level. Depth-first search (DFS) follows one path to its end before trying the next.

Candidates also report that the questions are written as Amazon stories. A question about packages, warehouses, or delivery routes is usually a plain array or graph question. The story does not change the algorithm, so write down the input, the output, and the size limits.

Design Gurus keeps a list of the coding questions Amazon asks most often, sorted by pattern.

A worked example in words

Suppose a question gives you a list of package weights and a class width. It asks how many packages belong to each weight class. Class 0 contains weights below the width, class 1 contains the next range, and so on.

The pattern is a hash map. Loop over the weights once. For each weight, divide by the class width to get the class number, then add one to that class's count in the map.

One pass over n packages costs linear time, written O(n). The map has at most one entry per class. Here is the same idea in Python.

from collections import defaultdict

def count_by_class(weights, width):
    counts = defaultdict(int)
    for w in weights:
        counts[w // width] += 1
    return dict(counts)

print(count_by_class([3, 7, 12, 14, 25], 10))

The function returns a dictionary from class number to count, and it never reads any package twice. For those five weights and a width of 10, it prints {0: 2, 1: 2, 2: 1}.

Most Amazon OA questions have this structure: one pass, one data structure, one clear cost. Grokking the Amazon Coding Interview practices these question types one pattern at a time, with worked solutions.

A time plan for the coding section

The new grad and intern versions give about 70 minutes for two questions. The SDE II version gives 90. The plan below is for 70 minutes; with 90, give each question 10 more minutes.

Read both questions first. Spend the first three minutes reading both before writing anything. Then start with the one that looks easier, since a finished easy question is worth more than a half-finished hard one.

Plan 25 to 30 minutes per question. Write the input and the output in one line each, name the pattern, then code it. If you have no fast solution after ten minutes, write the slow correct one first and improve it after.

Keep the last 10 minutes for testing. Try an empty input, a single item, all items equal, and the largest input size the question allows.

An edge case is an input at the limit of what the question allows. It is where a solution most often gives a wrong answer.

Prefer O(n log n) or better. The notation O(n log n) means the running time grows only a little faster than the input size n.

A solution that is O(n squared) grows with the square of n. It often takes too long on the largest test inputs and fails them.

The Work Simulation section

Candidates report that the Work Simulation is a set of short video scenarios about a working day. In each one you choose a response, or rank several responses from best to worst. The scenarios are judged against Amazon's Leadership Principles, the written list of behaviors Amazon expects from every employee.

Candidates also report that failing the Work Simulation fails the whole OA, whatever your coding result. So it deserves as much care as the code.

Answer as a good Amazon engineer would. Ask for data before you decide. Take responsibility for a problem until it is fixed, even when it started on another team.

Escalate, which means telling a manager or the right team, as soon as a customer is affected. Never ignore a message from a teammate or a customer.

Rank consistently. If you put "collect more data" first in one scenario, do not put "act at once" first in a similar one.

Read the Leadership Principles as they appear in the behavioral interview before the OA. The same principles are used to judge the Work Simulation, and the same answers are expected in the interviews later.

The Workstyles section

Candidates report that Workstyles is a series of statement pairs. Each pair shows two statements, and you pick the one that is more like you. The statements map to the same Leadership Principles.

There is no coding here, and what matters is consistency. Similar statements appear more than once in different words. Choose the answer that is true for you at work, and pick the same side each time.

The system design section for SDE II

The experienced SDE II version adds a system design section of about 15 minutes, and it is untimed. Fifteen minutes is not enough for a full design. Expect short questions rather than a whole design interview.

Be ready to explain three things in a few sentences each. They are how to scale a simple web service, where to store its data, and what to cache. The Amazon SDE levels guide explains what Amazon expects from an SDE II.

What happens after the OA

Amazon says it tells you within about two days. If you pass, the next step is usually a phone screen. That is a call with an engineer, with one coding question in a shared editor and a few Leadership Principle questions.

After the phone screen comes the onsite loop. That is a set of four or five interviews on one or two days. Each interview mixes a coding or design question with Leadership Principle questions.

One interviewer, called the Bar Raiser, comes from outside the hiring team. The offer needs that person's approval.

The Amazon interview questions guide describes each round of the loop. The Amazon behavioral interview questions post lists the Leadership Principle questions with example answers.

The OA questions and the interview questions come from the same set of patterns. Grokking the Coding Interview teaches those patterns one at a time. A new question then looks like one you have already solved.

Frequently asked questions

How long is the Amazon online assessment? The new grad version takes up to two hours, the intern version about 90 minutes, and the SDE II version about two hours. The coding section alone is 70 minutes for new grads and interns and 90 minutes for SDE II. Interns have no Work Simulation, which is why their version is shorter.

Can you use the internet during the Amazon OA? Amazon's page says you may use publicly accessible online resources during the coding section. You must not copy and paste code, and you must not use print screen. The code you submit has to be your own work.

How hard are the Amazon OA coding questions? Candidates report that they are usually easy to medium. They use common patterns like hash maps, sliding windows, sorting, heaps, and graph search. The difficulty is finishing two questions in 70 minutes, not any single hard idea.

What happens if you fail the Work Simulation? Candidates report that failing the Work Simulation fails the whole OA, even with a perfect coding result. Every section has to pass on its own. Give the video scenarios the same care as the code.

How long do you have to complete the Amazon OA? Seven days from the invitation email. Amazon says it tells you within about two days after you finish whether you are invited to interviews. Take the practice test first, since it does not count.

Is the Amazon online assessment proctored? No. It is unproctored, which means no person watches you while you take it. The rules still apply: no copying and pasting code, no print screen, and your own work only.

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