Amazon SDE Interview Process: Phone Screen to Offer

The Amazon SDE interview runs from a recruiter call through a technical screen to a virtual onsite "loop". Amazon's own prep pages describe the screen by level: an online assessment for SDE II, and a 60-minute technical phone screen for SDE III. The loop is four 55-minute interviews for SDE II and five for SDE III. Two things make Amazon different from other big tech loops: every single round scores you against the company's Leadership Principles, and one interviewer, the Bar Raiser, comes from outside the hiring team and effectively holds veto power. Plan for four to eight weeks from first call to decision.

Below is what each stage looks like, what gets asked, and where most candidates lose points. We run mock interviews all day, and the Amazon loop is the one where strong coders most often stumble on the behavioral half.

The loop at a glance

Stage	Format	Length	Focus
Recruiter screen	Phone call	20-30 min	Background, role, logistics
Online assessment	Async coding + work styles	70-120 min	Two coding problems and a work style survey; the SDE II version adds 20 min of system design scenarios
Phone screen (SDE III)	Live coding and design	60 min	Half Leadership Principles, half coding and system design
Onsite loop	4 interviews (SDE II) or 5 (SDE III)	55 min each	Coding, system/technical design, behavioral

Amazon's own prep pages describe the path by level: SDE II candidates take the online assessment and then go to the loop, while SDE III candidates take a 60-minute technical phone screen instead. Levels map roughly as SDE I (L4), SDE II (L5), and SDE III / Principal (L6+), with system design weight increasing sharply from L5 up.

Stage 1: Recruiter call and the online assessment

The recruiter screen is a fit and logistics conversation, not a technical filter. Expect questions about your current stack, why Amazon, and comp and location. Be ready to name a specific team or domain interest; it helps routing.

The online assessment (OA) is where the technical filter starts for junior roles. It is delivered async, usually through HackerRank or Amazon's own platform, and typically includes:

One to two coding problems (data structures and algorithms) with hidden test cases.
A "work styles" or Leadership Principles survey with situational, agree/disagree style questions.
Sometimes a short work simulation or debugging segment.

OA problems skew toward strings, arrays, hash maps, and greedy logic rather than exotic dynamic programming. Problems in the style of Longest Substring Without Repeating Characters (sliding window plus a hash set) and Hand of Straights (a greedy grouping problem you solve with a count map and a heap or ordered map) are representative of the difficulty band. Get these fully passing, not "mostly passing," because partial test coverage reads as a weak signal.

Stage 2: The technical phone screen

Amazon's SDE III prep page describes a 60-minute technical phone screen: half on the Leadership Principles and half on coding problems and system design, so time management matters.

The bar here is not just a correct answer. Amazon interviewers score problem-solving out loud, clean code, edge case handling, and complexity analysis. State your approach and its time and space cost before you type, then confirm the interviewer is on board. Silent coding is the most common way we see candidates tank an otherwise solvable question.

Typical phone screen problems match the mid-to-senior band in our Amazon bank: Add Two Numbers (linked list digit addition with carry handling), Reverse Integer and String to Integer (atoi), which both hinge on 32-bit overflow checks, and Longest Palindromic Substring (expand-around-center or DP). None are tricky for their own sake, but all reward crisp edge case handling: empty input, overflow, single character, and null nodes.

Stage 3: The virtual onsite loop

The loop is four 55-minute interviews for SDE II and five for SDE III, back to back or split across two days. Amazon's SDE II prep page describes it like this:

Three interviews evaluating logical and maintainable code, problem solving, and data structures and algorithms.
At least one question on software systems design.
Leadership Principles questions throughout, typically two or three from each interviewer.
Possibly a Bar Raiser, someone from another team focused on hiring quality.

The Bar Raiser is the structural feature people underestimate. This interviewer is a trained employee from a different org with no stake in filling the role, and their job is to keep the hiring bar consistent. They can sink an otherwise positive loop. Treat every round as if it were the deciding one, because in a debrief the Bar Raiser's assessment carries outsized weight.

Coding rounds in the loop push harder than the phone screen. This is where a staff-level problem like Median of Two Sorted Arrays shows up, which requires a real binary search on the partition of two arrays in O(log(m+n)), not a merge-and-index shortcut. Zigzag Conversion appears as a simulation and indexing test that looks easy and trips people on the row-direction bookkeeping.

Leadership Principles run through everything

This is the part strong engineers neglect. Amazon evaluates you against its Leadership Principles (there are 16, including Customer Obsession, Ownership, Dive Deep, Bias for Action, and Deliver Results), and behavioral questions appear in nearly every round, not just the designated behavioral ones. A coder who nails all the algorithms but gives vague, unstructured stories often gets a "no hire" or "inclined no."

Prepare a bank of 12 to 15 detailed stories from your own work, each usable for two or three principles, and deliver them in STAR format (Situation, Task, Action, Result) with concrete metrics. Interviewers are trained to probe with follow-ups like "what would you do differently" and "what was the data," so your stories need real depth, not a rehearsed headline. If you want a structured approach, our guide on the STAR method for engineers walks through full examples.

Common LP prompts:

"Tell me about a time you disagreed with your manager." (Have Backbone; Disagree and Commit)
"Describe a time you took on something outside your scope." (Ownership)
"Tell me about a time you missed a deadline." (Deliver Results; Earn Trust)

How to prepare (and what to skip)

Split your time roughly 60/40 between coding and behavioral. Most candidates over-index on rare dynamic programming and under-practice explaining their code and telling tight LP stories.

For coding, drill the patterns Amazon actually favors: sliding window, two pointers, hash-map counting, binary search, linked list manipulation, and greedy. You can practice these against the real Amazon set on our Amazon company page, and run full timed mocks on the practice tool so you get used to narrating under a clock.

A focused two to three week plan:

Week 1: Arrays, strings, hashing, two pointers, sliding window. Do Longest Substring Without Repeating Characters and Longest Palindromic Substring until they are automatic.
Week 2: Linked lists, binary search, greedy, and math/overflow problems (Add Two Numbers, Median of Two Sorted Arrays, Reverse Integer, String to Integer).
Week 3: System design at your level, plus writing and rehearsing your LP stories out loud.

Practice talking while you code. The Amazon rubric rewards communication as much as correctness, and it is the cheapest skill to improve.

FAQ

How many rounds is the Amazon SDE interview?

Amazon's own prep pages describe it by level: SDE II candidates take an online assessment and then a loop of four 55-minute interviews, and SDE III candidates take a 60-minute technical phone screen and then a loop of five 55-minute interviews. A recruiter call usually comes first.

What is the Amazon Bar Raiser?

The Bar Raiser is a trained interviewer from a team outside the one hiring you, present to keep the hiring standard consistent across the company. They evaluate both technical skill and Leadership Principles and carry strong influence in the debrief, including the ability to block an offer. Prepare for at least one round to be tougher and more probing than the rest.

How hard are Amazon coding questions?

Mostly medium difficulty, weighted toward strings, arrays, hash maps, linked lists, and greedy, with the occasional hard problem like Median of Two Sorted Arrays in the onsite loop. Amazon cares less about obscure tricks and more about clean code, edge cases, complexity analysis, and communication.

Do I really need to prepare Leadership Principles stories?

Yes. Behavioral questions appear in almost every round, and weak, unstructured stories sink candidates who code well. Prepare a bank of 12 to 15 STAR-format stories with real metrics, each usable for two or three of the 16 principles.

How long does the whole process take?

Typically four to eight weeks from the recruiter call to a decision, though it varies by team, level, and scheduling. The onsite loop itself is usually completed in one or two days, and debrief plus offer follow within days to a couple of weeks.