rollup-plugin-filesize

10.0.0 verified Mon Apr 27 auth: no javascript

A Rollup plugin that displays the size of output files in the CLI, including minified, gzipped, and Brotli sizes. Version 10.0.0 is the latest stable, requiring Node >=16 and Rollup >=4 (ESM-only). It offers customizable output formatting, a reporter API for custom handlers (e.g., badge generation), and experimental size comparisons against previous releases or builds. Differentiates from alternative size plugins with built-in Brotli support and theme-aware display.

Common errors

error Error [ERR_REQUIRE_ESM]: require() of ES Module not supported ↓

cause Package is ESM-only; CommonJS require fails.

fix

Use import syntax instead of require().

error TypeError: filesize is not a function ↓

cause Default import used but named import does not match.

fix

Use import filesize from 'rollup-plugin-filesize'.

error Error: Cannot find module 'rollup-plugin-filesize' ↓

cause Package not installed or incorrect path.

fix

Run npm install rollup-plugin-filesize --save-dev.

Warnings

breaking Version 10 drops CommonJS support; package is ESM-only. ↓

fix Use import syntax and ensure Node >=16.

breaking Version 6 drops terser for minification; minification is optional. ↓

fix If minification is needed, use a separate plugin like @rollup/plugin-terser.

deprecated The 'render' function option is deprecated; use 'reporter' instead. ↓

fix Replace 'render' with 'reporter' option.

gotcha For code-splitting builds, the plugin reports each file individually. ↓

fix Check console output for per-file sizes; aggregate manually if needed.

gotcha Windows compatibility fixed in v8.0.1 for import paths. ↓

fix Use v8.0.1 or later on Windows.

deprecated showBeforeSizes is experimental and may change. ↓

fix Do not rely on it for production use.

Install

npm install rollup-plugin-filesize

yarn add rollup-plugin-filesize

pnpm add rollup-plugin-filesize

Imports

filesize

wrong

const filesize = require('rollup-plugin-filesize');

correct

import filesize from 'rollup-plugin-filesize';

Package is ESM-only since v10; CommonJS require will fail.

filesize

wrong

import filesize from 'rollup-plugin-filesize';

correct

import { filesize } from 'rollup-plugin-filesize';

Named export available for tree-shaking; both work but named is preferred.

Plugin

wrong

import { Plugin } from 'rollup-plugin-filesize';

correct

import type { Plugin } from 'rollup';

Plugin type is from Rollup, not from this package.

Quickstart

Shows how to integrate the plugin into a Rollup build, displaying minified and gzipped sizes.

import { rollup } from 'rollup';
import filesize from 'rollup-plugin-filesize';

async function build() {
  const bundle = await rollup({
    input: 'src/index.js',
    plugins: [
      filesize({
        showMinifiedSize: true,
        showGzippedSize: true,
        showBrotliSize: false,
        theme: 'dark'
      })
    ]
  });
  await bundle.write({ file: 'dist/bundle.js', format: 'es' });
}

build().catch(err => console.error(err));