Exported Photos file size larger than expected

How are you exporting your photos? Are you exporting with "File > Export > Export unmodified Original" or with "File > Export > .. Photos"?

• The first option "Export unmodified Original" should be giving you the exactly identical original file and the same file size.
• The second option "File > Export > .. Photos" may result in larger or smaller file sizes, depending on the file format of the original and the quality settings.
  • If your photos are in the High Efficiency format HEIC, you will at least get twice the size on export, because HEIC needs only half the storage of a JPEG in the same quality. And Photos does not yet support the export of your iPhone photos in the original HEIC format.
  • If your photos are JPEGs and you export your photos as JPEGs, try the export settings below to avoid enlarging the files:

If you set "Jpeg Quality" to "maximum", the exported image file may have. larger file size as the original had, if the original has been a high compression applied. You will not get a better quality by using less compression than the original JPEG file had applied. For the typical JPEG the quality "High" will suffice to give a good quality and not increase the file size.