Amazon Front End Interview Questions
Find the latest version of this page on GreatFrontEnd's Amazon Front End Interview Guide.
Amazon's Front End interviews are known for their focus on technical depth and alignment with the company's Leadership Principles.
Understanding the Amazon Front End Interview Process
The interview process typically involves several stages:
- Online assessment (OA): This is a timed assessment that typically includes:
- Technical questions: Often coding challenges (e.g., LeetCode-style problems, UI component building). You are likely required to use Vanilla JavaScript.
- Systems design scenarios: Questions about design considerations, potentially multiple-choice or short written answers.
- Work style survey: Questions related to Amazon's Leadership Principles.
- Common questions: Accordion, Signup Form, Data Table, Todo List
- Technical phone screen: A 45-60 minute interview, usually with a hiring manager or a senior engineer. It's often split between:
- Behavioral questions: Based on Amazon's Leadership Principles.
- Front end coding problems: Whiteboard-style coding focusing on JavaScript, HTML, CSS, and DOM manipulation.
- Onsite interview (Loop): This is the main interview day, consisting of 4-5 rounds, each lasting about 55-60 minutes. The interview loop typically assesses both technical and non-technical competencies based on Amazon's Leadership Principles. Rounds often cover:
- Coding rounds: More complex Data Structures & Algorithms (DSA) problems (medium to hard difficulty), often with a front end focus.
- Front end fundamentals round: Deep dive into JavaScript, HTML, CSS, DOM, browser APIs, event loop, accessibility, and performance. You might be asked to build a small UI component or debug code.
- System design round (Front End Focused): Designing scalable and performant front end systems (e.g., a photo gallery, a type-ahead search). This is crucial for mid-to-senior level roles.
- Behavioral rounds / Leadership Principles: Several rounds dedicated to assessing your past experiences against Amazon's 16 Leadership Principles. One interviewer will likely be a "Bar Raiser."
Key areas to focus on
Front end fundamentals
Strong front end engineering fundamentals are essential. Be prepared for:
- HTML: Semantic HTML, accessibility (ARIA attributes), HTML5 features.
- CSS: Layout (Flexbox, Grid), Box Model, specificity, inheritance, responsive design, animations, performance optimization.
- JavaScript:
- Core concepts:
this, closures, prototypes, event loop, hoisting,var,let,const, scope. - ES6+ features: Promises, async/await, arrow functions, destructuring, spread/rest operators, Maps, Sets.
- DOM manipulation: Efficiently interacting with the DOM, event handling, event delegation.
- Browser APIs: Local Storage, Session Storage, Web Workers, Geolocation, etc.
- Performance: Debouncing, throttling, virtual DOM (if discussing frameworks), critical rendering path.
- Data structures & algorithms: Be comfortable with common data structures (arrays, strings, linked lists, trees, graphs) and algorithms (sorting, searching) and be able to implement them efficiently in JavaScript.
- Core concepts:
- Web performance: How to optimize page load times, rendering, and responsiveness.
- Accessibility (a11y): Understanding WAI-ARIA, semantic HTML, keyboard navigation, and how to build inclusive web experiences.
- Security: XSS, CSRF, CORS, secure coding practices for the front end.
- Front end frameworks (e.g., React, Angular, Vue.js): While the focus is often on vanilla JavaScript for coding, be prepared to discuss component lifecycle, state management, and performance optimizations within your chosen framework.
System design
This round assesses your ability to design scalable and performant front end applications. Be prepared to discuss:
- Scalability: How your design handles increasing user load, data, and features.
- Modularity: Breaking down a large application into smaller, manageable components.
- Performance: Optimizing initial load, subsequent interactions, and data fetching.
- Reliability/Resilience: Handling errors, network issues, and ensuring a stable user experience.
- Maintainability: Writing clean, testable, and understandable code.
- Accessibility: Integrating accessibility best practices into the design.
- Trade-offs: Justifying your design choices and understanding the implications of different approaches (e.g., client-side vs. server-side rendering, specific data structures, caching strategies).
Behavioral Questions & Leadership Principles (LPs)
Amazon heavily emphasizes its 16 Leadership Principles. A significant portion of the interview will focus on how you've demonstrated these principles in past roles, as "past behavior is the best predictor of future success."
The STAR Method is crucial. For every behavioral question, structure your answer using the STAR method:
- Situation: Describe the context of the situation.
- Task: Explain the task or challenge you faced.
- Action: Detail the specific actions you took to address the task.
- Result: Describe the positive outcome of your actions, ideally with quantifiable metrics.
Key Leadership Principles to focus on (and have 2-3 strong STAR examples for each):
- Customer Obsession
- Ownership
- Invent and Simplify
- Are Right, A Lot
- Learn and Be Curious
- Hire and Develop the Best
- Insist on the Highest Standards
- Think Big
- Bias for Action
- Frugality
- Earn Trust
- Dive Deep
- Have Backbone; Disagree and Commit
- Deliver Results
- Strive to be Earth's Best Employer
- Success and Scale Bring Broad Responsibility
Official guides
For more detailed information directly from Amazon, refer to Amazon's official interview preparation guides for:
Source: Glassdoor Amazon Front End Engineer Interview Questions
Questions
Questions sourced from the web and the GreatFrontEnd community.
Quiz questions
- What is the CSS box model?
- Read answer (Free)
- What is a JavaScript closure?
- Read answer (Free)
- What happens when you type URL into a browser and hit enter?