Amazon OA Questions 2021: What Candidates Actually Saw
Last updated: May 2026
318+ Amazon online assessment questions reported by candidates who took the OA in 2021. Sourced from 1Point3Acres, LeetCode, Blind, Glassdoor, and Reddit. Data grows as new reports are added.
Amazon OA Format in 2021
The Amazon online assessment has followed a consistent format across multiple hiring cycles. Based on 2021 reports in the database, candidates typically see 2 to 3 algorithmic coding problems delivered through a proctored online platform (most commonly HackerRank). Some roles include additional behavioral or work-simulation components after the coding section.
Time limits reported by candidates range from 70 to 110 minutes for the full assessment. The coding problems are auto-graded, so edge case handling and runtime efficiency both matter. Partial credit is available on some platforms if your solution passes a subset of test cases.
Real Amazon OA Questions from 2021
Amazon OA
Ques: https://aonecode.com/interview-question/maximum-bounded-array ``` def MaxBoundedArray(n, low, up): \ttotal = (up - low) * 2 + 1 \tif (n > total or up < low or n < 3): \t\treturn None \t# if above check is passed,...
Amazon OA
Given four arrays of integers and an integer limit. We need to pick 1 number from each of the four arrays such that the sum of the selected numbers is...
Amazon OA
Given four arrays of integers and an integer limit. We need to pick 1 number from each of the four arrays such that the sum of the selected numbers is...
Amazon OA
Amazon Frontend OA Prob 1: Given an array of strings input : ["Jacky" , "Jack", "Jackster"] and a query : ["Jack"] return number of string items for which query is the...
Amazon OA
Optimizing Alexa Suggestions 2. Demolition Robot
Amazon OA
Q1 Four and two wheels Q2 Given a encoded string and decode it Input: "mnes--ya-----mi" *Output: "my name is" Explaination: [[m, n, e, s, -], [-, y, a, -, -], [-, -, -, m, i]] Read from...
Amazon OA
Debugging Section - 7 Ques (20 minutes) This section was very esay. You do not need to prepare for it separately. \t 2. Coding Section - 2 Ques (70 minutes) ...
Amazon OA
Is there anyone who has faced similar issue while giving OA on hackerrank. The same code passed for other 16 testcases but gave compile error in one testcase. Is it even...
Amazon OA
Took an online test today. Q1 was about given an Array of numbers, for example {5, 1, 2, 1, 4, 5} which represent skills of employees..(Skills[i]) How many teams you can...
Amazon OA
I gave Amazon OA today on Hackerrank platform. There were two questions to be done in 105 min followed by a work-performance evaluation I believe. Could be related to Amazon...
Amazon OA
Hello All, I can\'t remember the wording of the exact question, but the idea was to generate all contiguous subarrays of a given array. For all contiguous subarrays, find the maximum...
Amazon OA
1st Question: Find the maximum number of overlapping windows in a set of windows. I.e. 1 --- 10 2 --- 8 3 --- 4 Answer would be 2 ( 3 --- 4 window is overlapped...
Amazon OA
Question 1: Find the all numbers in maximum intersections for given intervals. Ex:[[1,5],[5,10],[5,5]]: the maximum intersection is [5,5] and there\'s only 1 number in it so answer is 1. Ex[[1,2],[3,5]] no intersection and the answer...
Amazon OA
I gave amazon OA today. Could pass all test cases in one ques and only 20 out of 24 in another ques Whats the probability of getting shortlisted to next round? P.S: Questions...
Amazon OA
More example: Anyone got an idea how to solve this? I still haven\'t fully understood this question.
Amazon OA
Get the sum of min and max diff for all subarrays [2,4,3,5] wrong: sum = (4 - 2) + (4 - 3) + (5 - 3) + (3 - 2) + (5...
Amazon OA
Can anyone share amazon OA questions for USA. I have an OA coming up and the leetocde link has been removed. Really appreciate anyone\'s help on this. Thank you!
Amazon OA
prob 1: https://algo.monster/problems/amazon_oa_find_all_combination_of_numbers_sum_to_target Should be O(N^3). I did not pass the tests per TLE prob 2: https://leetcode.com/discuss/interview-question/1148760/items-in-containers-amazon-oa \\* and | problem. Given a string with \ and | and 2 arrays of startIndices and...
Amazon OA
Two questions (105 mins) 1. Fleet of vehicles - https://leetcode.com/discuss/interview-question/1365052/Amazon-OA 2. https://leetcode.com/problems/rank-transform-of-an-array/ but worded differently SDE II, USA
Amazon Interview
Hello, If we passed the Online Assessment and failed in the Phone Interview/Virtual Interview. Do we have to pass the Online Assessment again if we apply for other position? Thanks in...
Topic Breakdown (2021 OA)
Topics reported by candidates who took the Amazon OA in 2021:
Difficulty Breakdown (2021 OA)
102
easy
27
hard
11
medium
Difficulty labels are reported by candidates or inferred from LeetCode ratings.
How to Prepare for the Amazon OA
The Amazon OA is a timed, auto-graded coding test. Preparation is different from interview prep: you need to optimize for both correctness and speed, since partial credit requires passing test cases, not just showing reasoning.
- Practice timed sessions. Set a timer for 35 to 45 minutes per problem and simulate the real constraint.
- Focus on the topic clusters that appear most in Amazon OA reports: dynamic programming, graphs, arrays, and strings make up the majority of reported problems.
- Read the problem constraints carefully before writing code. The constraints often reveal the expected time complexity and algorithm type.
- Use the LeakCode database to review 2021 OA questions from actual candidates. Pattern recognition across multiple sightings is a stronger prep signal than any single mock problem.
- If the OA includes a work simulation section, practice under realistic conditions. This section tests judgment and values alignment, not coding ability.
FAQ
What does the Amazon OA look like in 2021?
Based on 2021 candidate reports, the Amazon OA typically includes 2 to 3 coding problems and runs 70 to 110 minutes. Topics lean toward dynamic programming, graphs, arrays, and strings. Some roles include a work simulation section after the coding component.
How long is the Amazon OA?
Most candidates report 70 to 90 minutes for the coding component. Roles with additional work simulation sections extend the total time to 110 to 150 minutes. Check your invitation email for the exact time allocation for your specific role.
What platform does Amazon use for the OA?
Amazon uses HackerRank or its own proprietary platform depending on the role and hiring cycle. Your invitation will specify the platform. Both platforms support multiple languages including Python, Java, C++, and JavaScript.
Are these real Amazon OA questions?
Yes. All questions in the LeakCode database come from candidate reports on 1Point3Acres, Blind, Glassdoor, Reddit, and LeetCode. They are not AI-generated. Each question links to its source where available.
Other Amazon OA Years
Related: Amazon OA Hub · Amazon All Questions · All OA Questions · Data Sources