Bulk Image Compressor

What is the Bulk Image Compressor?

The Bulk Image Compressor shrinks a whole set of JPG, PNG and WebP files in one go. Drop in a folder, set the quality once, watch each file’s before and after size, and download everything as a zip. It is built for the job of trimming an image library before a site launch or a migration, when running images through a single-file tool one at a time would take an afternoon. Every file is processed in your browser, so nothing is uploaded and there is no cap on how many you can do.

How to use it

1. Drag a set of images onto the drop zone, or click to select several.
2. Set the quality (75 to 85 for photos) and, optionally, a maximum width so oversized originals are scaled down too.
3. Choose whether to keep each file’s format or convert everything to WebP.
4. Click Compress All. The list shows each file’s new size and the percentage saved, plus a total.
5. Download the zip, or individual files.

Features

• One setting, many files, with per-file results so you can spot the outliers.
• Optional resize combined with compression, which is where most of the savings come from.
• Convert to WebP across the batch for the smallest output.
• Zip download that keeps original filenames.
• Private and unlimited: no upload, no account, no quota.

A safe workflow for a whole library

Compressing hundreds of images is easy to get wrong in a way you only notice weeks later. Keep the originals somewhere safe before you start. Test the setting on ten representative images, including a screenshot and a photo with fine detail, and zoom in before you trust it. Compress by content type rather than all at once: photos at quality 78 in WebP, screenshots and diagrams as PNG or WebP lossless. Check the total saving is worth the effort; if a folder is already small, leave it. Then replace the files and purge your cache. The full procedure, including how to do this on WordPress without breaking existing image sizes, is in how to bulk compress an entire image library without ruining anything.

Related tools

Change dimensions for a batch with the Bulk Image Resizer, compress a single image with a live preview in the Image Compressor, and convert one file’s format with the Image Converter.

Frequently asked questions

How many images can I compress at once?

There is no fixed limit. A few hundred web-size images is fine on a laptop; memory is the constraint on phones.

Will PNGs lose quality?

PNG output is lossless unless you resize or convert to WebP. Converting a PNG to lossy WebP is where the big savings are, at a small visual cost.

Is EXIF data kept?

No. Camera and GPS metadata are stripped when the image is re-encoded.

Are my images uploaded?

No. Everything happens in the browser; you can disconnect after the page loads.