gzip-size

What is gzip-size?

The gzip-size npm package allows you to easily calculate the compressed size of a string or buffer using gzip compression. This can be particularly useful for assessing the size of files or assets in web development, ensuring that your resources are optimized for performance by evaluating their size after compression.

What are gzip-size's main functionalities?

Get the compressed size of a string

This feature allows you to calculate the gzip-compressed size of a string. It's useful for quickly assessing how much space a piece of text will take up after compression.

const gzipSize = require('gzip-size');
const string = 'Hello, world!';
gzipSize(string).then(size => {
  console.log(`Compressed size: ${size} bytes`);
});

Get the compressed size of a file

This feature calculates the gzip-compressed size of a file's contents. It's particularly useful for web developers looking to optimize their assets for performance by understanding the size impact of compression.

const gzipSize = require('gzip-size');
const fs = require('fs');

fs.readFile('file.txt', 'utf8', (err, data) => {
  if (err) {
    throw err;
  }
  gzipSize(data).then(size => {
    console.log(`Compressed size: ${size} bytes`);
  });
});

Synchronous API for getting compressed size

gzip-size also offers a synchronous API, allowing for immediate calculation of the compressed size without dealing with promises. This can be handy for scripts and applications where asynchronous handling is not necessary or desired.

const gzipSize = require('gzip-size');
const string = 'Hello, world!';
const size = gzipSize.sync(string);
console.log(`Compressed size: ${size} bytes`);

Other packages similar to gzip-size

compressing

The 'compressing' package is a comprehensive compression library that supports gzip, tar, zip, and tgz formats. While it offers broader functionality in terms of supported formats, it might be more complex to use when you only need to calculate gzip sizes.

zlib

Node's built-in 'zlib' module provides compression functionality, including gzip compression. While it is not an npm package, it serves a similar purpose. However, 'gzip-size' simplifies the process specifically for calculating the size of compressed content, making it more convenient for this specific use case.

brotli-size

Similar to 'gzip-size', 'brotli-size' calculates the size of a string or buffer after compression, but using the Brotli algorithm instead of gzip. This package is useful for those looking to compare or utilize Brotli compression, which can offer better compression ratios for certain types of content.

README

gzip-size

Get the gzipped size of a string or buffer

Install

$ npm install --save gzip-size

Usage

var gzipSize = require('gzip-size');
var string = 'Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.';

console.log(string.length);
//=> 191

console.log(gzipSize.sync(string));
//=> 78

API

gzipSize(input, callback)

input

Required
Type: string, buffer

callback(err, size)

Required
Type: function

gzipSize.sync(input)

Returns the size.

input

Required
Type: string, buffer

CLI

$ npm install --global gzip-size

$ gzip-size --help

  Usage
    gzip-size <file>
    cat <file> | gzip-size

  Example
    gzip-size index.js
    211

Tip

Combine it with pretty-bytes to get a human readable output:

$ pretty-bytes $(gzip-size jquery.min.js)
29.34 kB

License

MIT © Sindre Sorhus