How to prepare images for the web

Why it’s useful: Optimizing images for the web improves download times for users and saves server space. UMaine requires all images to be 3M or less before uploading to our web server.

On a Mac

What you’ll need: Preview (free program for the Mac)


  1. Launch Preview, then File/Open an image
  2. Duplicate the image (work on the copy to keep the original unchanged)
  3. Tools/Adjust Size
  4. Resolution: 72 (bigger is not better)
    Width (pixels): = 1000
    Resulting size: <1M
  5. File/Save: Rename, save to desktop or folder; format = jpg; quality = best

On a PC

What you’ll need: a built-in PC program


Free online image compressors

Additional Resources