Whenever you export a JPG you’re asked to choose a quality number, and nobody explains what it means. Is 100 the best? Is 60 too low? The honest answer is that the number matters less than you’d think, as long as you stay in the right range.
What the number actually does
JPG compresses an image by discarding fine detail that human eyes are least likely to notice. The quality setting controls how aggressively it does that. A higher number discards less and gives a bigger file. A lower number discards more and gives a smaller file but introduces visible flaws like blocky patches, fuzzy edges and color banding.
One caveat: the scale isn’t universal. A 80 in one program isn’t necessarily identical to an 80 in another, because each program implements it slightly differently. Treat the numbers as a rough guide and judge by eye.
Why 100 isn’t worth it
Going from 85 to 100 makes the file much larger, often double or more, while the improvement is almost impossible to see at normal viewing size. You pay in file size for detail nobody will notice. Quality 100 also isn’t lossless, because JPG always loses something, so it’s an expensive way to feel safe.
A practical range
- 85 to 95: high quality. Good for photography portfolios, images that will be printed, or anything you may edit and re-save later.
- 75 to 85: the sweet spot for most websites and blogs. Looks very close to the original and the file is far smaller.
- 60 to 75: fine for thumbnails, email attachments and situations where file size is the priority. Flaws start to become findable if you look closely.
- Below 60: visible damage in most photos. Use only when a strict size limit forces you to.
What kind of image you have changes things
Photos with soft gradients, like a sky, show banding when over-compressed. Photos with fine texture, like foliage or fabric, hide compression better. Images with text or sharp lines look rough at lower qualities, and may be better as PNG. When in doubt, compare the output at 100% zoom, not shrunk to fit your screen, since problems hide when you zoom out.
How to find your number quickly
- Export at 80.
- Zoom to 100% and look at edges, skies and faces.
- If it looks clean, try 70. If it looks rough, try 85.
- Stop when you reach the lowest setting that still looks fine.
Resize first, then pick quality
Dimensions have a bigger impact on file size than quality does, so get the size right before fine-tuning the number. If you’re trying to hit a specific size limit, the step-by-step approach in how to resize an image to 100KB shows the order to work in.
Avoid saving JPGs over and over
Each save at lower quality compounds the damage. Keep an original, and export a fresh JPG from it every time instead of re-saving an already-compressed one. This is one of the common image resizing mistakes worth avoiding.
What about WebP?
WebP uses a similar quality scale and usually produces a smaller file at the same visual quality. If you serve images on a website, it’s worth switching. Our WebP conversion guide shows how.
Set your quality, resize and download in one step with our free image resizer.