Image compressor by KB is a simple tool that lets you resize and compress images in bulk by specifying the exact file size in kilobytes. It automatically compresses and adjusts resolution while keeping the best possible quality. Perfect for meeting upload limits on websites, emails, and apps.
Privacy: All image processing is executed entirely client-side using in-browser technologies (e.g., JavaScript). Image data never leaves your device, is not transmitted over the network, and is not written to or stored on any server. This ensures full privacy and security, as all operations occur within your local browser environment.
Simply drag and drop or click on the file picker to choose up to 20 images, and then select a target size in KB. After you click on Compress, you will see the images compressed to your desired size. You can download all the images at once in a ZIP file. We also offer conversion to JPEG, PNG, GIF, and WebP.
We strive to preserve quality as much as possible, but if the gap between the original file size and the target size is too large, some loss of quality will be inevitable.