Amazon OA (Online Assessment): How to Pass

The Amazon Online Assessment, the OA, is the work-from-home screen Amazon sends after you apply and before the interview loop. It is one link, sat in your own time, and it is graded before a human ever reads your resume closely. Nobody watches you live while you take it. It is still a timed, one-sitting assessment on Amazon's platform, and using outside help breaks the terms you agree to. Most people think of it as "the coding test," which is the trap: two of its three parts have nothing to do with algorithms, and both of those are scored against the same Leadership Principles the interviewers use later. Prepare for it the way you would prepare for a short loop.

There are three components: a timed coding section, a Work Styles survey, and a Work Simulation. What you get depends on the role and the level. New-grad and SDE I candidates see all three. SDE II assessments swap the Work Simulation for a short system-design block. And plenty of experienced hires never get an OA at all, going straight to a phone screen or the loop instead. The exact shape moves by team, req, and year, so read the list below as the common case rather than a fixed script.

What the OA contains

The single most common mistake is spending the whole budget on the two coding problems and clicking through the survey and simulation on autopilot. Those two parts are a real gate. Plenty of candidates who ace the code get stopped there.

The Work Styles survey

About 38 statements, each rated on a scale. It looks like a personality quiz. The answers are mapped to the Leadership Principles and scored like a behavioral round. When a statement asks whether you would ship with incomplete information or wait for the full picture, remember which company wrote Bias for Action. Answer honestly, in Amazon's language, and stay consistent. The survey comes back to the same themes from different angles, and a set of answers that contradict each other reads as someone gaming the rubric.

The Work Simulation

Here you work through a stream of work emails and tickets as if you already had the job, deciding what to handle first. Nothing gets marked right or wrong in green. Each choice is read against the Leadership Principles, so the reply that scores is the one an Amazonian would send. Escalate when a customer is affected, and look at the data before you decide. When an ambiguous ticket lands, take ownership of it instead of passing it along. New-grad and SDE I candidates see this part; SDE II assessments usually replace it with a design block of roughly 15 to 20 minutes.

The coding section, specifically

You get two problems and about 70 minutes, at easy-to-medium difficulty. Unlike the live rounds later in the loop, the OA editor runs your code against hidden tests, so a working solution beats a clever one that does not compile. That inverts your usual instinct. The grader sees passing tests and nothing else, so elegance earns you no points here. Finish both problems to a passing state before you polish either one.

Amazon reuses a small set of patterns, and the OA draws from the same well as the loop. The shapes below come up again and again. Read them as the kinds of problem to expect rather than a list of the exact questions you will get.

• Graphs and grids. BFS and DFS over a matrix or an adjacency list: counting connected regions, a shortest path through a grid, flood fill, state that spreads step by step. The most common shape on the OA.
• Arrays and hashing. Frequency counts, two-pointer sweeps, prefix sums, and the hash-map lookup that turns a nested loop into one pass.
• Strings. Parsing and transforming text, sliding-window scans, anagram and palindrome checks.
• Trees and intervals. Traversals, level-order walks, and merging intervals show up regularly. Heavy dynamic programming is de-emphasized, so do not over-index on it.

The fastest prep is to drill the patterns Amazon repeats rather than grinding a generic list. Start with Graphs & Grids, then work through Arrays, Hashing & Strings and Trees; What Amazon Tests ranks the full pattern list by how often it appears. Recognising a grid traversal or a hash-map lookup on sight is what leaves time at the end for edge cases.

Amazon OA for interns vs new grads vs SDE II

The OA changes shape with the level you applied for, and so does whatever comes after it. Amazon's ladder starts at L4 (SDE I); there is no L3, and SDE II is L5. Here is the common case for each pipeline.

For students the OA is the main event. Interns and new grads face a coding bar set at medium and a loop with less in it, so a strong assessment does more of the work for you. An OA link can also arrive within days of applying through university recruiting, so have your prep done before you submit. The Internship & New-Grad lesson covers that path end to end. Your team and req can still change the shape. Ask your recruiter.

What happens after the Amazon OA

Once you submit, the scoring is automatic. Nothing more is asked of you until results come back. If you pass, what comes next depends on your pipeline (see the table above). Experienced hires usually get a phone screen next, typically one coding problem plus a couple of Leadership Principle questions. New grads and L4 candidates often skip it and go straight to the loop.

The loop is where most of the weight sits. A full-time loop is four interviews of about 55 minutes, virtual by default. Each round usually opens with 10 to 20 minutes of Leadership Principle questions before the technical part. One of the interviewers is the Bar Raiser, a trained interviewer from outside the hiring team who leads the debrief and can veto the hire. The complete Amazon interview process walks through every stage from application to offer.

How long until you hear back

OA results usually come back within one to a few weeks. The spread depends on the team and on how many candidates are in the pipeline. A quiet first week is normal. From application to final decision, the whole Amazon process typically takes four to eight weeks. Once you have sat the loop, the debrief usually happens 4 to 7 days later, and the decision follows a few business days after that.

If you are declined, Amazon applies a cool-off period before you can reapply for a similar role, commonly reported as around six months, though the exact window depends on the role and the pipeline you came through. Amazon rarely tells candidates why they were turned down, so write down what felt shaky while it is fresh. Reapplying carries no stigma.

Is the Amazon OA difficult?

The coding itself is not the hard part. Easy-to-medium problems, generous time, and a pattern set that repeats mean a prepared candidate clears the code with room to spare. What filters people is everything around it. Some run out of time because they polished problem one and never finished problem two. Others submit code that fails hidden edge cases they never tested, or treat the survey and simulation as throwaways when both are graded against the Leadership Principles. The bar is getting all three parts right.

How to pass the Amazon OA

Common questions about the Amazon OA

What is on the Amazon OA?

Three parts, all taken from home. First comes a coding section of two problems in roughly 70 minutes, graded on hidden test cases. Then a Work Styles survey of about 38 rated statements. Last, a Work Simulation of realistic tickets and emails, which SDE II candidates usually swap for a short design block. Only the first part is coding; the other two score you against the Leadership Principles.

What coding questions does the Amazon OA ask?

Easy-to-medium problems from a small set of patterns that repeat. Graphs and grids lead, arrays and hashing and strings come up constantly, and trees and intervals appear regularly. Heavy dynamic programming is de-emphasized, so drill the common patterns instead of a generic problem list.

Is the Amazon OA proctored, and can you look things up?

No person watches you live. It is still timed and taken in one sitting on Amazon's platform, and outside help breaks the terms you accept when you start. The loop later asks you to solve similar problems out loud, and a gap between your OA and your live performance is easy to spot. Solve it yourself.

How long does the Amazon OA take?

Two to three hours, in one sitting. The coding section alone is roughly 70 minutes for two problems, and the survey and the simulation take most of the rest. Start it only when you can finish without being interrupted.

Does everyone get an Amazon OA?

No. It is standard for internship, new-grad and SDE I pipelines. Many experienced hires skip it and go straight to a phone screen or the loop. Whether you get one depends on the team and the role. Ask.

The Amazon angle

The OA looks like a coding test and grades like a loop because Amazon front-loads the Leadership Principles into every stage, the automated ones included. A candidate who aces the two problems and rushes the survey can still be gated, because the survey and simulation carry real weight and both point at the LPs. So the prep that moves your OA score most is knowing what Amazon measures: the 16 Leadership Principles and the way hiring decisions get made. Another LeetCode set adds less.