Image Compression Quality Settings Explained
Understand quality controls, visual artifacts, and why the best setting depends on how an image will be used.
Quick answer
Higher quality keeps more detail but creates a larger file. Lower quality shrinks the file but can add visible artifacts. Choose the setting based on the image size on screen and how closely people will look at it.
Quality is a trade-off
Higher quality generally preserves more image detail but creates a larger file. Lower quality can produce a much smaller file, but repeated edges, fine textures, and gradients may show compression artifacts.
Pick the setting for the destination
A small preview thumbnail can tolerate more compression than a portfolio image. A website hero image may need a different balance again. Choose the quality based on how large the image will appear and how closely people will inspect it.
What artifacts look like
Know what to look for so you can spot problems quickly.
- • Blocky squares in flat areas such as skies or walls.
- • Fuzzy halos around text and sharp edges.
- • Banding, where smooth gradients become visible steps.
- • Loss of fine texture in hair, fabric, or foliage.
Use visual inspection
File size alone cannot tell you whether an image is acceptable. Always inspect the compressed version at the intended viewing size before replacing the original.
Frequently asked questions
- What is a good quality setting for web images?
- A moderate setting works for most web images. Test a few levels and pick the lowest one that still looks clean at display size.
- What are compression artifacts?
- Artifacts are visible flaws such as blockiness, blurry edges, or banding in gradients caused by removing image detail.
- Does recompressing an image damage it further?
- Yes. Each lossy pass can add artifacts, so compress from the original whenever possible.