Here are some things that explain how to upload your scans to AutoCropper.
To batch upload multiple scans at once, go to AutoCropper.io/crop-scans and click one of the Upload buttons:
Then select multiple files in the upload dialog like this:
Read more about holding shift during file selection to select multiple files.
You can upload a single crop by clicking the Upload Button in the center of the preview placeholder, or on the bottom toolbar:
And then select an individual scan image file:
The current supported upload file types are JPEG, PNG, and gif.