I recently discovered a new tool on Product Hunt called Smart Upscaler. I uploaded some headshots for an org chart that were less than 30 KB and was impressed with the results. It took the file below from 26.5 KB to 1.26 MB.
It’s free to use and uploaded images are stored securely and deleted as soon as processing has completed.
Check it out for yourself – https://icons8.com/upscaler