Practice React interviews
36 hands-on exercises across 12 topics. Write code in the editor, see it run live, and submit for feedback on every requirement, with minimal fixes you can apply in one click.
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01
JSX & Components
Describe UI with JSX and split it into small components.
02
Props & Composition
Pass data down and compose components with children.
03
State (useState)
Keep component state and update it immutably.
04
Effects (useEffect) & Lifecycle
Synchronize with the outside world and clean up.
05
Events & Forms
Handle events and build controlled inputs.
06
Lists & Keys
Render collections with stable keys, filter and sort them.
07
Conditional Rendering
Show, hide and switch UI based on state.
08
Refs (useRef)
Reach DOM nodes and keep values across renders.
09
Context API
Share state across the tree without prop drilling.
10
Custom Hooks
Extract reusable stateful logic into hooks.
11
Performance
useMemo, useCallback and React.memo to avoid wasted work.
12
Data Fetching
Load data with loading and error states, and avoid races.