Often images can be compressed more for viewing on a full HD Screen (TV or PC), resulting in a smaller file without differences for the human eye.
Viewers can't see any difference in the quality.
Files take up much space, copying and loading is slower.
Quality 100% File size: 1'200 KB |
Quality 90% File size: 410 KB |
Quality 80% File size: 270 KB |
Details begin to be lost. However, on most pictures, viewers probably won't see any difference in the quality.
Quality 70% File size: 220 KB |
Quality 60% File size: 180 KB |
Quality 50% File size: 160 KB |
Images getting fuzzy.
Quality 40% File size: 140 KB |
Quality 30% File size: 120 KB |
Quality 20% File size: 90 KB |
For viewing on a HD screen, a quality around 60% will bring the smallest file without any noticeable lost of quality.