🌐 Interview Prep

Web & Frontend

HTML, CSS layout, the DOM, HTTP, browsers, React, security and accessibility: front-end and full-stack interview staples.

📘 Learn it from scratch

Visual, hands-on lessons for every pattern in this topic. Do the lesson, then come back and the questions click.

HTML: Structure & SemanticsForms & InputsThe Box ModelCSS Layout with FlexboxResponsive Design for PhonesHTTP: Requests & ResponsesState, Events & Reducers

100 questions, most asked first

Ranked by how often each question comes up in real interviews. #1 is the most common.

Any difficulty Easy Medium Hard

All patterns HTTP & APIs Storage & caching Box model Flexbox Web security React HTML Accessibility Responsive design CSS Grid & positioning Browser & performance State management Forms DOM & events

#2What makes an API RESTful?HTTP & APIsEasyFree #3Cookies vs localStorage vs sessionStorageStorage & cachingEasyFree #4The CSS box modelBox modelEasyFree #5Flexbox vs CSS GridFlexboxEasyFree #7HTTP methods and status codesHTTP & APIsEasyFree Unlock 26 more Web & Frontend questions · all 1,200 questions for $39/year (about 11¢ a day)See full access #13State vs propsReactEasy🔒#15Why do lists need keys?ReactEasy🔒#17Semantic HTMLHTMLEasy🔒#19Responsive designResponsive designEasy🔒#20CSS position valuesCSS Grid & positioningEasy🔒#21display none vs visibility hidden vs opacity 0Box modelEasy🔒#25Lazy loading images and codeBrowser & performanceEasy🔒#32SEO for web developersHTMLEasy🔒#37Form validation on the client and the serverFormsEasy🔒#38CSS units (px, em, rem, %, vw/vh)Responsive designEasy🔒#40Pseudo-classes vs pseudo-elementsBox modelEasy🔒#41CSS transitions vs animations vs JS animationBrowser & performanceEasy🔒#43DOM APIs every frontend dev should knowDOM & eventsEasy🔒#46Loading, empty and error statesState managementEasy🔒#50401 vs 403 (and 404 for privacy)HTTP & APIsEasy🔒#53What is a CDN?Storage & cachingEasy🔒#55ClickjackingWeb securityEasy🔒#64Lifting state up and prop drillingState managementEasy🔒#67Debugging with browser DevToolsBrowser & performanceEasy🔒#72Cross-browser compatibilityResponsive designEasy🔒#73The viewport meta tagResponsive designEasy🔒#75How do you center a div?FlexboxEasy🔒#78Form submission and preventDefaultFormsEasy🔒#91Mobile-first designResponsive designEasy🔒#92Accessible formsAccessibilityEasy🔒#93Color contrast and accessible colorAccessibilityEasy🔒