Automatically compress all PNG images on your website with SmallPNG software.

The SmallPNG software provides an automatic solution to compress all PNG images on your website. By converting images to an efficient 8-bit PNG format with alpha channel, SmallPNG significantly reduces file sizes, often up to 60-80% smaller than 24/32-bit PNG files. The compressed images generated are fully standards-compliant and supported by all web browsers and operating systems.

Properly optimised image files can improve performance and reduce bandwidth usage for your website. Optimisation is an easy and worthwhile effort that can be done losslessly, with no quality loss and an end result that looks exactly the same as the original. So, there's no excuse for not doing it.

If you have a large folder of images, including sub-folders and sub-sub-folders, SmallPNG can quickly optimize all the images recursively in a directory. SmallPNG is a command-line utility and a library that uses lossy compression of PNG images to reduce file sizes, often by as much as 70%. The software preserves full alpha transparency, and the generated images are compatible with all web browsers and operating systems.

SmallPNG comes with a range of highlight features that make it a powerful tool for PNG image compression. The software's palette generation relies on a combination of vector quantization algorithms to produce high-quality results.

SmallPNG also uses an adaptive dithering algorithm, which is unique in that it adds less noise to images than the standard Floyd-Steinberg algorithm.

The software is easy to integrate with shell scripts, GUIs and server-side software, making it a versatile solution for developers who need to optimize their images.

Additionally, SmallPNG's fast mode allows for real-time processing of large numbers of images, making it a convenient and time-efficient option for web developers who need to compress many images at once.

Recursively Optimize PNG Files using SmallPNG command
SmallPNG's command-line utility is an excellent tool for optimizing PNG files and improving website speed while reducing bandwidth usage. One of its greatest advantages is its lossless optimization, which means that the PNG files maintain their quality throughout the process, making it an ideal solution for web developers.

The software is especially useful when dealing with large numbers of PNG files, including those within sub-directories. Manually optimizing such files using traditional tools like GIMP or other image editors can be a daunting and time-consuming task.

SmallPNG, however, is the go-to PNG optimization tool for Windows, Unix, and Linux users. Its recursive optimization feature allows for fast and easy optimization of PNG files, making it a popular choice among web developers.

What does SmallPNG do?
SmallPNG is a tool that utilizes intelligent lossy compression techniques to reduce the size of your JPEG, PNG, and WEBP files. By selectively decreasing the number of colors in the image, the software reduces the number of bytes required to store the data. Although the effect is barely visible to the naked eye, it has a significant impact on the size of the file.

Why should I use SmallPNG?
PNG is a valuable image format because it's the only widely supported format that allows for partially transparent images. However, despite using compression, PNG files can still be quite large, which can negatively impact the performance of your apps and websites. This is where SmallPNG comes in - the software can effectively shrink images, allowing for reduced file sizes, lower bandwidth usage, and faster loading times.

How does it work?
SmallPNG works by utilizing a technique called "quantization" to combine similar colors in your uploaded PNG (Portable Network Graphics) file. This process effectively reduces the number of colors in the image, enabling the conversion of 24-bit PNG files to much smaller 8-bit indexed color images. In addition to color reduction, the software also removes all unnecessary metadata from the file.

As a result, the software produces high-quality PNG files with full support for transparency, while also significantly reducing the file size. With SmallPNG, users can enjoy the best of both worlds - high-quality images that take up less space.

Is it supported everywhere?
SmallPNG produces files that are compatible with all modern web browsers, including mobile devices, and can be displayed without any issues. Even if you need to support older browsers like Internet Explorer 6, which typically ignores PNG transparency and displays a solid background color, SmallPNG can help. The software ensures that the background becomes transparent again, resulting in binary transparency without the need for any workarounds. This means that your images can be viewed seamlessly across all platforms, making it an ideal choice for optimizing images for the web.

What Does It Mean to Optimize Images?
Optimizing images involves reducing their file size to speed up the load time of your web pages, which can improve the user experience. Large images can slow down your website, making it less efficient for users. SmallPNG software offers lossy and lossless compression methods to decrease the file size of images, which can help to improve page load times. By optimizing images, you can create a more streamlined and faster website that provides a better user experience.

$ smallpng --help

usage:  smallpng [options] [ncolors] -- pngfile [pngfile ...]
         smallpng [options] [ncolors] - ]stdout [stdin

options:
   --force           overwrite existing output files (synonym: -f)
   --skip-if-larger  only save converted files if they're smaller than original
   --output file     destination file path to use instead of --ext (synonym: -o)
   --ext new.png     set custom suffix/extension for output filenames
   --quality min-max don't save below min, use fewer colors below max (0-100)
   --speed N         speed/quality trade-off. 1=slow, 4=default, 11=fast & rough
   --nofs            disable Floyd-Steinberg dithering
   --posterize N     output lower-precision color (e.g. for ARGB4444 output)
   --strip           remove optional metadata (default on Mac)
   --verbose         print status messages (synonym: -v)

SmallPNG can quantize one or more 32-bit RGBA PNG files to 8-bit (or smaller) RGBA-palette, which reduces the file size without any loss in quality. The name of the output file will be the same as the input file, but with an extension of "-fs8.png", "-or8.png", or a custom extension if specified. If the input file is provided via standard input (stdin), the quantized image will be sent to standard output (stdout).

To process a single file and output the quantized image to stdout, the special output path "-" can be used along with the input file. If the output file already exists, the default behavior is to skip the conversion. However, the "--force" option can be used to overwrite the output file.