Free online tool

Batch Image Compressor

Fit images within a 50 KB upload limit or set your own per-image target.

Upload a file

Drop your file hereTap to choose a file

or click to browse, or paste from the clipboard

JPG, JPEG, PNG, WEBP, AVIF, TIFF, TIF

Max file size: 10 MiB

Batch download

Process up to 20 images in upload order and download one ZIP with all outputs.

Fit a 50 KB upload limit

Enter 48 in the KiB target field to keep each image within 49,152 bytes, below a 50 KB upload limit.

Honest size report

The ZIP includes JSON and readable text reports with original bytes, output bytes, savings, dimensions, and quality.

Control dimensions

Set maximum width and height while preserving each image’s aspect ratio. Small images are not enlarged.

How to batch compress images to a ZIP

  1. 1

    Add 1–20 still JPG, PNG, WebP, AVIF or TIFF images within the upload and pixel limits.

  2. 2

    Choose JPG, PNG or WebP output and maximum width and height. Images keep their proportions and are not enlarged.

  3. 3

    Set the maximum JPG/WebP quality. For a 50 KB upload limit, enter 48 in Target per image (KiB). Leave it empty to skip the size target.

  4. 4

    Convert and download the ZIP. If any target fails, adjust settings and retry the batch.

  5. 5

    Open compression-report.txt or compression-report.json to compare measured image sizes; ZIP overhead is excluded.

What people use this tool for

  • Prepare product photos for a website.
  • Resize a group of images for email or upload limits.
  • Compare image compression results in a downloadable report.

Frequently Asked Questions

How do I compress several images at once?

Add 1–20 still images, select JPG, PNG or WebP output and set the maximum width and height. Optionally enter a target in KiB for each image. Convert and download a ZIP containing the images and size reports.

How do I compress an image to 50 KB?

Choose JPG or WebP, enter 48 in Target per image (KiB) and convert. This sets a per-image cap of 49,152 bytes. To use the full 50,000-byte allowance, enter 48.828125 instead. Extract the ZIP and upload the image inside. If the target cannot be reached, reduce the maximum width and height and try again.

Does compression always make an image smaller?

No. Changing formats or processing an already optimized image can increase size. Reports show negative savings when this happens. ZIP overhead is excluded from image totals.

What happens if my target cannot be reached?

No partial ZIP is returned. The error identifies the image number that failed. Increase the target, reduce the maximum dimensions or choose JPG/WebP. Target search can lower JPG/WebP quality; PNG encoding is lossless for the resized pixels, and the quality control does not affect PNG.

Are transparency and animation preserved?

PNG and WebP preserve transparency. JPG flattens transparency onto white. Animated and multiple-page inputs are rejected; this tool accepts still images.

What are the limits?

Up to 20 files, 10 MiB per file, 100 MiB combined, 24 million pixels per image, and 100 million source pixels per batch. Maximum output width and height are 4096 pixels. Processing stops after 90 seconds.

Is the image batch uploaded?

Yes. The selected images are uploaded to the server. The ZIP download is temporary; save it promptly. Input metadata is not copied into the generated image files.