Image Compressor

This is a free image compressor that reduces an image’s file size without compromising its quality. Upload an image, select your compression level, view the output, and download the optimised image for the web, social media, documents or other digital applications.

Smaller images can be stored, shared and transferred more easily. Optimising images can also be beneficial for websites to help visitors download less data.

How to Use the Image Compressor

1. Add an image – drag a file onto the dropzone or click it to browse. JPG, PNG, WebP, GIF and BMP are all accepted.

   

2. Set the quality – the slider runs from 1 to 100 and starts at 75. You can also choose whether the result comes out as JPEG or WebP.

   

3. Check the preview – look at the compressed version at full size before you trust the number, since the point at which quality starts to show varies by image.

   

4. Compare the sizes – the readouts show the original size, the compressed size and the percentage saved.

   

5. Download the image – one button saves the compressed file to your device.

   

What Is Image Compression?

The data required to store an image can be reduced by image compression. These are available in 2 main types:

• Lossless: Saves the image data exactly as it was taken, and so the file is smaller in size.
• Lossy compression: discards some of the image data to reduce file size and can result in a slight loss of quality.

JPEG typically is lossy, and PNG traditionally is lossless. WebP also has both options.

Why Compress Images?

Compressing images is worth doing when you want to:

• Cut the weight of a page without changing how it looks.
• Speed up how quickly images load.
• Save storage space
• Make files easier to share and email.
• Minimize amount of data transferred

The compression depends on the image format, size, content and of course previous compression.

JPEG, PNG, WebP and AVIF

JPEG: For photographs and other images that contain lots of colors.

PNG: Appropriate for logos, screenshots, graphics and transparency or lossless quality.

WebP: Lossy/lossless compression, can offer smaller files for many kinds of images.

AVIF: designed to be efficient at compressing images and includes transparency and animation features.

The right format depends on the image, the quality you need and what you have to stay compatible with. This tool writes JPEG or WebP; AVIF is worth knowing about but is not one of the output options here.

Image Compression vs. Resizing

Resizing an image changes the width and height of the image, but compression decreases the amount of data in an image.

Resizing an image before or during compression may greatly decrease file size if the image is significantly bigger than it needs to be to be displayed. In such a case, a large photo of 4000 × 3000 pixels doesn’t necessarily need to be that big if it will be viewed at a smaller 800 × 600 pixel size.

Image Compression Best Practices

Do:

1. Keep the original of any image that matters.
2. Compare the compressed image to the original image.
3. Choose an appropriate format.
4. Resize an image first when it is far larger than it will ever be displayed.
5. Adjust compression for a quality vs size compromise.

Don’t:

1. Always use the same compression level for all images.
2. Compress important images repeatedly and without checking the quality.
3. Apply heavy compression if small details are important!
4. Pay attention to the percentage reduction and not actual image quality.

Frequently Asked Questions