Production Data Fetching: When to Pick React Query or SWR

React and Next.js developers constantly face the choice between React Query and SWR for data fetching, with no universal answer. This guide clarifies when simplicity wins—SWR's 4KB footprint for standard use cases—versus when advanced features justify complexity, particularly React Query's sophisticated caching and mutation handling for data-heavy applications. The right choice directly impacts bundle size, development velocity, and application performance.