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How do you analyze and reduce bundle size in Next.js?

Q: How do you analyze and reduce bundle size in Next.js?

**TL;DR.** Use @next/bundle-analyzer to **visualize** bundles, then shrink them: keep components as **Server Components** (zero client JS), **lazy-load** heavy client code with next/dynamic , avoid large deps/**barrel imports**, and move logic **server-side**. Check the **build output's** per-route JS sizes. analyze bundle-analyzer reduce RSC + dynamic + lighter deps</text

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Understand the problem

Bundle analyzer, RSC, and dynamic imports.

nextjsbundle-sizeperformanceoptimization

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Read the code

Enable the analyzer + avoid barrel imports

// next.config.js
const withAnalyzer = require('@next/bundle-analyzer')({ enabled: process.env.ANALYZE === 'true' });
module.exports = withAnalyzer({ /* ... */ });
// run:  ANALYZE=true next build

// ❌ pulls the whole library
import { debounce } from 'lodash';
// ✅ imports only what you need
import debounce from 'lodash/debounce';

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