Vite Bundle Analyzer

A bundle analyzer for Vite, Rollup, and Rolldown that visualizes bundle size with an interactive treemap.

[!WARNING] Vite enables minification by default. The parsed size may appear larger than actual size because bundle info from Rollup isn't compressed. Rolldown support is experimental.

Installation

npm install vite-bundle-analyzer -D
# or
yarn add vite-bundle-analyzer -D
# or
pnpm add vite-bundle-analyzer -D

Usage

Vite

import { defineConfig } from 'vite'
import { analyzer } from 'vite-bundle-analyzer'

export default defineConfig({
  plugins: [
    analyzer()
  ]
})

Rollup

import { adapter } from 'vite-bundle-analyzer'
import { analyzer } from 'vite-bundle-analyzer'

export default {
  plugins: [
    adapter(analyzer())
  ]
}

Rolldown Plugin (Experimental)

import { unstableRolldownAdapter } from 'vite-bundle-analyzer'
import { analyzer } from 'vite-bundle-analyzer'

export default {
  plugins: [
    unstableRolldownAdapter(analyzer())
  ]
}

Configuration

Option	Type	Default	Description
`analyzerMode`	`'server' \| 'static' \| 'json' \| function`	`'server'`	Analysis output mode
`fileName`	`string \| function`	`'stats'`	Output filename (without extension)
`reportTitle`	`string`	`'Vite Bundle Analyzer'`	Report page title
`gzipOptions`	`Record<string, any>`	`{}`	Gzip compression options (see zlib module)
`brotliOptions`	`Record<string, any>`	`{}`	Brotli compression options
`analyzerPort`	`number \| 'auto'`	`8888`	Server port
`openAnalyzer`	`boolean`	`true`	Auto-open browser (server/static mode only)
`defaultSizes`	`'stat' \| 'gzip' \| 'brotli'`	`'stat'`	Default size metric
`summary`	`boolean`	`true`	Show summary in console
`enabled`	`boolean`	`true`	Enable/disable plugin
`include`	`string \| RegExp \| Array<string \| RegExp>`	`[]`	Include patterns
`exclude`	`string \| RegExp \| Array<string \| RegExp>`	`[]`	Exclude patterns
`pathFormatter`	`(path: string, defaultWd: string) => string`	`undefined`	Formatting Paths

CLI

npx vite-bundle-analyzer

# With options
npx vite-bundle-analyzer --help

Common Issues

Empty Chunk Sizes

If chunk sizes appear empty, check for plugins that break source maps (e.g., @vitejs/plugin-legacy). The analyzer relies on source maps for accurate size calculation.

Vite-based Frameworks

For frameworks built on Vite (VitePress, Remix, Qwik), use analyzerMode: 'server' for accurate results due to multiple build instances.

Static Mode Without Server

When analyzerMode: 'static' and openAnalyzer: false, no development server is created.

API Integration

import { SSE, createServer, injectHTMLTag, openBrowser, renderView } from 'vite-bundle-analyzer'

// Create custom server
const server = createServer()
server.get('/', async (c) => {
  const html = await renderView(data, { title: 'Custom Analyzer', mode: 'stat' })
  c.res.writeHead(200, { 'Content-Type': 'text/html' })
  c.res.write(html)
  c.res.end()
})
server.listen(3000)

Debug

# Vite
vite build --debug

# Environment variable
ANALYZE_DEBUG=true npm run build