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Challenge your web knowledge.

Work through focused development, design, accessibility, security, and workflow quizzes with immediate feedback and detailed explanations. Your progress stays on this device, so you can leave and continue later.

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Search by concept or filter by category. New quiz topics can be added to this library as it grows.

JavaScript Core

JavaScript Fundamentals: Values, Scope & Functions

Test the JavaScript rules that shape everyday code: types, coercion, scope, closures, objects, and function behavior.

15 questionsIntermediate18 min

Advanced JavaScript

Async JavaScript: Promises, Tasks & the Event Loop

Reason through Promise chains, async functions, timers, error flow, cancellation, and event-loop ordering.

15 questionsIntermediate–Advanced20 min

Browser JavaScript

DOM & Browser JavaScript: Events, Forms & Web APIs

Challenge your understanding of event propagation, DOM updates, forms, selectors, storage, accessibility, and browser behavior.

15 questionsIntermediate18 min

Google Apps Script

Google Apps Script Fundamentals & Services

Test the runtime, authorization model, built-in services, logging, web apps, and core patterns used in Apps Script projects.

10 questionsIntermediate14 min

JavaScript Core

JavaScript Arrays, Objects & Data Transformations

Challenge your understanding of immutable updates, array methods, references, destructuring, Maps, Sets, and reliable data pipelines.

10 questionsIntermediate–Advanced15 min

Advanced JavaScript

JavaScript Prototypes, Classes & Modules

Reason through prototype lookup, class behavior, private fields, inheritance, module bindings, imports, and reusable code boundaries.

10 questionsAdvanced16 min

JavaScript Practice

JavaScript Testing, Debugging & Error Handling

Test assertions, async tests, mocks, stack traces, error design, debugging tools, and strategies for trustworthy JavaScript.

10 questionsIntermediate–Advanced15 min

Advanced JavaScript

JavaScript Performance, Memory & the Browser

Reason about measurement, rendering work, event handlers, memory retention, workers, data structures, and scalable frontend performance.

10 questionsAdvanced16 min

Google Apps Script

Apps Script for Google Sheets Automation

Work through challenging questions about ranges, values, batching, formulas, filters, and reliable spreadsheet automation.

10 questionsIntermediate–Advanced15 min

Google Apps Script

Apps Script Triggers, APIs & Reliable Automation

Test trigger identities, event objects, locks, caching, external requests, advanced services, and production automation design.

10 questionsAdvanced16 min

CSS Layout: Grid, Flexbox & Sizing

Reason through intrinsic sizing, Grid tracks, Flexbox alignment, overflow, containing blocks, and robust layout choices.

10 questionsIntermediate–Advanced15 min

CSS Cascade, Specificity & Maintainable Styles

Master cascade layers, specificity, inheritance, custom properties, selectors, and architecture decisions that keep CSS predictable.

10 questionsAdvanced15 min

Responsive, Accessible & Modern CSS

Test container queries, logical properties, media preferences, fluid sizing, focus styles, and resilient responsive design.

10 questionsIntermediate–Advanced15 min

Semantic HTML, Forms & Document Structure

Test landmark structure, forms, tables, metadata, responsive images, and the semantics that make HTML resilient.

10 questionsIntermediate14 min

Web Accessibility & Inclusive Interfaces

Challenge your knowledge of WCAG principles, keyboard interaction, ARIA, focus, contrast, announcements, and accessible components.

10 questionsIntermediate–Advanced15 min

Web Development

HTTP, REST APIs & Web Communication

Reason through methods, status codes, caching, headers, authentication, idempotency, CORS, and API design.

10 questionsIntermediate–Advanced15 min

Web Security Fundamentals for Developers

Test XSS, CSRF, authentication, authorization, cookies, password storage, headers, validation, and secure design decisions.

10 questionsIntermediate–Advanced16 min

Developer Workflow

Git Branching, History & Collaboration

Challenge your Git knowledge with commits, branches, merges, rebases, recovery, remotes, conflicts, and collaborative workflows.

10 questionsIntermediate–Advanced15 min

SQL & Relational Database Fundamentals

Test joins, keys, normalization, indexes, transactions, aggregation, NULL behavior, and safe query design.

10 questionsIntermediate–Advanced15 min

Modern PHP Web Development

Challenge your PHP knowledge with types, arrays, requests, sessions, PDO, namespaces, errors, security, and web application structure.

10 questionsIntermediate15 min

Frontend Frameworks

React Components, State & Effects

Test component rendering, props, state, keys, effects, context, controlled inputs, and practical React design decisions.

10 questionsIntermediate–Advanced15 min

Web Performance & Core Web Vitals

Reason through loading, rendering, images, JavaScript, caching, metrics, fonts, and evidence-based performance improvements.

10 questionsIntermediate–Advanced15 min

UX, Interface Design & Design Systems

Test usability, hierarchy, feedback, forms, navigation, research, tokens, components, and coherent interface systems.

10 questionsIntermediate14 min

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More than a final score

Each answer explains the underlying rule, shows why the correct choice works, and helps you recognize the same concept in real code.

1

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Questions focus on behavior and reasoning rather than trivia alone.

2

Review immediately

Read the explanation while the problem and your reasoning are still fresh.

3

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