svgo

What is svgo?

The svgo npm package is a Node.js-based tool for optimizing SVG vector graphics files. SVGO stands for Scalable Vector Graphics Optimizer. It works by applying a series of transformations and optimizations to SVG files to reduce their size without affecting their visual quality. This is particularly useful for web development, where smaller file sizes can lead to faster load times and better performance.

What are svgo's main functionalities?

Minify SVG files

This feature allows you to minify SVG files by removing unnecessary data without affecting the rendering of the SVG. The code sample demonstrates how to use the optimize function to minify an SVG string.

const { optimize } = require('svgo');
const svgString = '<svg ...> ... </svg>';
const result = optimize(svgString, { path: 'path/to/svg/file.svg' });
console.log(result.data);

Remove specified attributes

This feature allows you to remove specified attributes from SVG elements. The code sample shows how to use the removeAttributesBySelector plugin to remove the 'fill' attribute from all elements that have it.

const { optimize } = require('svgo');
const svgString = '<svg ...> ... </svg>';
const result = optimize(svgString, {
  plugins: [
    {
      name: 'removeAttributesBySelector',
      params: {
        selector: '[fill]',
        attributes: 'fill'
      }
    }
  ]
});
console.log(result.data);

Prettify SVG files

This feature allows you to prettify SVG files by reformatting them with consistent indentation and spacing. The code sample demonstrates how to use the js2svg option with the pretty parameter set to true.

const { optimize } = require('svgo');
const svgString = '<svg ...> ... </svg>';
const result = optimize(svgString, {
  plugins: [
    'preset-default',
    'sortAttrs',
    {
      name: 'removeAttrs',
      params: { attrs: '(stroke|fill)' }
    }
  ],
  js2svg: { pretty: true }
});
console.log(result.data);

Other packages similar to svgo

imagemin-svgo

imagemin-svgo is a plugin for Imagemin, which is a general image optimization framework. While svgo focuses solely on SVG files, Imagemin can handle various image formats when combined with the appropriate plugins. Imagemin-svgo brings the capabilities of svgo to the Imagemin ecosystem.

svg-sprite

svg-sprite is a package that takes a set of SVG files and combines them into a single sprite sheet. While svgo optimizes individual SVG files, svg-sprite focuses on creating an efficient way to bundle multiple SVGs for use on the web.

svg-crowbar

svg-crowbar is a tool designed to extract SVG elements from an HTML document and download them as standalone SVG files. It is different from svgo, which optimizes existing SVG files rather than extracting them from HTML.

README

SVGO

SVGO, short for SVG Optimizer, is a Node.js library and command-line application for optimizing SVG files.

Why?

SVG files, especially those exported from vector editors, usually contain a lot of redundant information. This includes editor metadata, comments, hidden elements, default or suboptimal values, and other stuff that can be safely removed or converted without impacting rendering.

Installation

You can install SVGO globally through npm, yarn, or pnpm. Alternatively, drop the global flag (global/-g) to use it in your Node.js project.

# npm
npm install -g svgo

# yarn
yarn global add svgo

# pnpm
pnpm add -g svgo

Command-line usage

Process single files:

svgo one.svg two.svg -o one.min.svg two.min.svg

Process a directory of files recursively with -f/--folder:

svgo -f path/to/directory_with_svgs -o path/to/output_directory

Help for advanced usage:

svgo --help

Configuration

SVGO has a plugin architecture. You can read more about all plugins in Plugins | SVGO Documentation, and the default plugins in Preset Default | SVGO Documentation.

SVGO reads the configuration from svgo.config.js or the --config path/to/config.js command-line option. Some other parameters can be configured though command-line options too.

svgo.config.js

module.exports = {
  multipass: false, // boolean
  datauri: 'base64', // 'base64'|'enc'|'unenc'
  js2svg: {
    indent: 4, // number
    pretty: false, // boolean
  },
  plugins: [
    'preset-default', // built-in plugins enabled by default
    'prefixIds', // enable built-in plugins by name

    // enable built-in plugins with an object to configure plugins
    {
      name: 'prefixIds',
      params: {
        prefix: 'uwu',
      },
    },
  ],
};

Default preset

Instead of configuring SVGO from scratch, you can tweak the default preset to suit your needs by configuring or disabling the respective plugin.

svgo.config.js

module.exports = {
  plugins: [
    {
      name: 'preset-default',
      params: {
        overrides: {
          // disable a default plugin
          removeViewBox: false,

          // customize the params of a default plugin
          inlineStyles: {
            onlyMatchedOnce: false,
          },
        },
      },
    },
  ],
};

You can find a list of the default plugins in the order they run in Preset Default | SVGO Documentation.

Custom plugins

You can also specify custom plugins:

svgo.config.js

const importedPlugin = require('./imported-plugin');

module.exports = {
  plugins: [
    // plugin imported from another JavaScript file
    importedPlugin,

    // plugin defined inline
    {
      name: 'customPlugin',
      params: {
        paramName: 'paramValue',
      },
      fn: (ast, params, info) => {},
    },
  ],
};

API usage

SVGO provides a few low level utilities.

optimize

The core of SVGO is optimize function.

const { optimize } = require('svgo');

const result = optimize(svgString, {
  path: 'path-to.svg', // recommended
  multipass: true, // all other config fields are available here
});

const optimizedSvgString = result.data;

loadConfig

If you write a tool on top of SVGO you may want to resolve the svgo.config.js file.

const { loadConfig } = require('svgo');

const config = await loadConfig();

You can also specify a path and customize the current working directory.

const config = await loadConfig(configFile, cwd);

Other ways to use SVGO

Method	Reference
Web app	SVGOMG
Grunt task	grunt-svgmin
Gulp task	gulp-svgmin
Webpack loader	image-minimizer-webpack-plugin
PostCSS plugin	postcss-svgo
Inkscape plugin	inkscape-svgo
Sketch plugin	svgo-compressor
Rollup plugin	rollup-plugin-svgo
Visual Studio Code plugin	vscode-svgo
Atom plugin	atom-svgo
Sublime plugin	Sublime-svgo
Figma plugin	Advanced SVG Export
Linux app	Oh My SVG
Browser extension	SVG Gobbler
API	Vector Express

Donors

SheetJS LLC	Fontello

License and Copyright

This software is released under the terms of the MIT license.

Logo by André Castillo.