Amazon SDE 1 OA Questions 2026: What the Assessment Actually Tests

If you are searching for Amazon SDE 1 OA questions 2026, you want the online assessment, not the full loop. The OA is the filter Amazon uses before a human ever watches you code. It is timed, it is scored by hidden tests, and a lot of strong LeetCode grinders still fail it because they prepared for the wrong section.

This guide is the shape of the Amazon SDE 1 online assessment as candidates describe it: a coding section, a work-style section, and — for some 2026 invitations — a separate bug-fixing module. It is not a leaked paper. Amazon changes modules by role, location, and hiring drive. Use it to know what to practice, then check what people are posting this week on Amazon interview questions.

Amazon SDE 1 OA questions in 2026

New grad and SDE 1 invitations usually land in three pieces. You may not see all three.

Piece	What it is	What "good" looks like
Coding assessment	Timed problems on HackerRank, most often two	Correct, reasonably efficient code that passes hidden tests
Work style / work simulation	Situational choices tied to Leadership Principles	Consistent, specific judgment — not a cartoon "always act" persona
Bug fixing	A newer module some candidates are seeing in 2026	You can find a defect and prove the fix. See the AI assistant bug fixing round

The coding section is the one people mean when they say "Amazon OA questions." The work-style section still rejects people. Do not leave it for the night before.

How the coding section is structured

Candidates commonly report:

Two problems in one sitting
A fixed timer (long enough for two mediums if you do not thrash, short enough that a stuck brute force will not finish)
Any mainstream language HackerRank offers
Hidden tests beyond the samples
Partial credit on some problems, all-or-nothing on others — you will not know which

You do not get an interviewer to hint. The only feedback is the sample tests you choose to run. That changes how you should work:

Read both problems before you commit. If one is a standard pattern and the other is a wall, bank the standard one first.
Write the brute force only if you can also see the optimization. A correct O(n^2) that times out on the last tests is a common SDE 1 miss.
Test the edges yourself: empty input, one element, duplicates, negatives, the maximum constraint.
Leave five minutes to reread the return type. Off-by-one and "return the index vs the value" are how passing local samples still fail.

Difficulty sits around easy-medium and medium. Hard DP shows up less often than arrays, hash maps, trees, and graphs.

Question patterns worth practicing

These are families, not a claim that any one prompt is on this week's OA. They match the level of coding problems already written up from Amazon loops, including distance between two nodes in a binary tree and the array-range problem in that same guide.

Arrays, prefixes, and hash maps

A large share of SDE 1 OA questions are "do this in one pass with extra memory."

Practice shape: given an array, count the number of subarrays whose sum equals k.

A nested loop is correct and too slow once n is large.
Keep a running prefix sum and a map of how many times each prefix has occurred.
At index i, the number of subarrays ending here with sum k is the count of prefix sum - k.

If you can explain that out loud in two minutes, you can handle most of the "variant of two-sum / subarray sum" prompts.

Also drill: group frequencies, pair elements that differ by k, merge intervals, and sliding window with a character budget.

Trees

Amazon likes trees because the code is short and the bugs are real: null children, visiting a node twice, mixing "path from root" with "any path."

Practice:

Lowest common ancestor
Distance between two nodes (LCA plus depths)
Level order with a twist (rightmost node, zigzag, max width)
Validate a BST, including duplicates and the full min/max range — not just parent vs child

Graphs

Expect BFS more often than a clever shortest-path algorithm.

Practice:

Number of islands / flood fill
Shortest path in an unweighted grid (BFS)
Course schedule / cycle detection
Clone a graph

If the problem says "minimum steps," try BFS before Dijkstra. If every edge has a weight, stop and reconsider.

Heaps and intervals

Top-k, merge k sorted lists, and "meeting rooms" show up because they test whether you reach for a heap instead of sorting on every query.

What you can deprioritize

For an SDE 1 OA, do not spend your last week on segment trees, heavy string algorithms, or obscure DP. Spend it on clean implementations you can write from a blank editor in 25 minutes, because that is the actual constraint.

The work style assessment

After the code, most SDE 1 candidates get a work style survey or a longer work simulation. The questions are workplace scenes. You pick what you would most likely do and what you would least likely do, or you rank responses.

They are written around Amazon Leadership Principles: ownership, customer obsession, dive deep, disagree and commit, earn trust, deliver results, and the rest.

A useful way to answer:

Prefer the option that owns the outcome and checks the data over the option that escalates immediately or stays silent.
Prefer a specific action ("pull the last 50 orders and see if the bug is in retries") over a vague one ("sync with stakeholders").
Do not pick the extreme on every question. "Always ship tonight" fails Bias for Action's partner, which is not breaking production. "Always wait for consensus" fails Bias for Action.
Stay consistent. The survey notices when you claim ownership in one scene and hide in the next.

There is no trick phrase to memorize. People fail this section by answering as the candidate they think Amazon wants, then contradicting that person three questions later.

If you are a fresher and your stories are college projects rather than production incidents, read Amazon SDE 1 interview questions for freshers before you invent office scenarios you have never lived.

A two-week plan for the SDE 1 OA

Days 1–3. Twenty array / hash map problems, timed at 30 minutes, in the language you will use on HackerRank. No IDE autocomplete if you can help it. HackerRank's editor is plainer than yours.

Days 4–6. Fifteen tree problems and ten graph problems. Implement LCA, BFS on a grid, and cycle detection until they are boring.

Days 7–8. Heaps and intervals. Write a min-heap solution and a sort-then-scan solution for the same prompt so you can pick the right one under a timer.

Days 9–10. Two full mocks: two problems, 90 minutes, no solutions open. Score yourself only on hidden-test thinking — did you test empty input before you "finished"?

Days 11–12. Work-style practice. Take ten Leadership Principles and write one real scene for each from a project, internship, or class. You will need those scenes again in the loop. The OA survey is the warm-up.

Day 13. Read live Amazon reports and only add a pattern if you have seen it more than once.

Day 14. Rest the syntax. Skim your own templates for BFS, binary search, and prefix sums. Sleep.

After you pass

A pass usually leads to a phone screen or straight into a loop: coding plus Leadership Principles, and sometimes a light design conversation. That is a different exam. The OA does not ask you to narrate. The phone screen does.

When you get the invite, switch material:

Coding-plus-LP loop: Amazon SDE 2 interview experience 2026 (the principles are the same at SDE 1; the design bar is higher at SDE 2)
Worked Amazon problems: Amazon SWE interview questions
Stories that do not sound like slogans: how to tell your story without clichés

Frequently asked questions

How many Amazon SDE 1 OA questions are there?

The coding portion is usually two problems. A separate work-style assessment follows for most candidates. Some 2026 invitations also include a bug-fixing section. Read the email; the modules are listed there.

What language should I use?

The one you can debug without documentation. Java, Python, and C++ are all common. Switching languages the week of the OA to match a blog post is how people fail sample tests they would have passed at home.

Does the OA include Leadership Principles?

Not as a spoken interview. The work-style questions are the written version of the same principles. Treat them as part of the assessment, not as a formality after the "real" test.

Are Amazon OA questions repeated?

Variants repeat more than exact prompts. Subarray sums, tree traversals, and grid BFS have been in the mix for years. Exact wording changes, which is why a static list goes stale and the Amazon questions page is the thing to recheck.

What score do I need to pass?

Amazon does not publish a cutoff, and anyone quoting one is guessing. Aim for both problems correct under the constraints, plus a work-style section that does not contradict itself. Partial credit exists on some coding problems, so a finished easy plus a solid attempt at the medium is better than an unfinished "optimal" draft.

Final thoughts

Amazon SDE 1 OA questions in 2026 are still a coding test plus a judgment test. The coding is pattern recognition under a timer. The judgment section is whether your choices sound like someone who owns an outcome.

Practice the patterns above until you can write them in a plain editor. Then look at what candidates are reporting right now on Amazon interview questions. Good luck.