Free Online Batch Image Compressor

Reducing image sizes individually can be time-consuming, especially when you are preparing an entire product catalogue, blog post or website gallery. The DevToolbox Batch Image Compressor allows you to process up to 20 images together in one session.

Add your files, select the required compression level and let the tool optimise each image inside your browser. Once processing is complete, you can compare the original and compressed sizes before downloading the results.

1. Drag and drop your images into the upload area or click to select files from your device.

2. Use the compression slider to set your preferred image quality.

3. Click “Compress Images” to process the selected files.

4. Review the new file size and reduction percentage shown for each image.

5. Click “Download All” to save the compressed images in a ZIP file.

Free users can process up to 20 images in a single batch.

The Batch Image Compressor supports the most commonly used web image formats:

• JPG and JPEG

• PNG

• WebP

Each compressed image keeps its original format. For example, a PNG file remains PNG after compression, while a WebP file remains WebP.

The quality slider lets you control the balance between image clarity and file size. A higher setting preserves more visual detail, while a lower setting generally creates a smaller file.

The default 80% setting works well for most website images, product photographs and blog graphics. If an image contains small text or fine details, consider using a higher quality setting. For thumbnails and other small web images, a lower setting may be sufficient.

The amount of compression will depend on the original file. An image that has already been optimised may not become significantly smaller.

Images larger than 1,920 pixels in width or height are resized proportionally during compression. This helps produce practical file sizes for websites, online stores, blogs and digital sharing.

Images that are already within the 1,920-pixel limit retain their existing dimensions.

Keep a copy of the original image if you require its full resolution for printing, professional editing or archival purposes.

Unoptimised images can make web pages slow to load, particularly for visitors using mobile devices or slower connections. Compressing images before uploading them reduces the amount of data the browser needs to download.

Smaller images can help you:

• Improve page-loading speed

• Reduce bandwidth usage

• Prepare product photographs for online stores

• Optimise blog and landing-page images

• Reduce the size of email attachments

• Make image collections easier to store and share

• Improve the browsing experience on mobile devices

Always review the compressed result before publishing it to ensure that important details remain clear.

Your images are processed locally inside your browser using JavaScript and Web Workers. They are not uploaded to the DevToolbox server for compression or storage.

This local approach is useful when working with personal photographs, client assets, unpublished designs, product images or screenshots that you do not want to send to an external processing server.

The time required to complete a batch depends on your device, browser and the number and size of the selected images.

• Compress multiple images at the same time

• Process up to 20 images on the free plan

• Adjust the image quality before compression

• Compare original and compressed file sizes

• View the reduction percentage for every image

• Download multiple results in one ZIP file

• Process images locally in your browser

• Use the tool without installing software

• No account required for basic compression