How compressing to a target size works
Quality is lowered before size because a slightly softer image at full resolution usually looks better than a smaller image. Files that are already under your target are left untouched.
Example: a 4 MB phone photo, 4032 × 3024 px, has to go under 1 MB for an email form. At JPG quality around 80 it usually lands at about 0.8 to 1 MB with no visible change. Asked for 100 KB, the same photo would need to shrink to roughly 1200 px wide.
Common size limits
| Where | Limit |
|---|---|
| YouTube thumbnail uploaded from a phone | 2 MB (50 MB from a computer) |
| X (Twitter) images | 5 MB |
| Twitch profile banner, offline screen | 10 MB |
| Discord attachment, free account | 20 MB |
| Many job and government forms | Often 100 KB to 2 MB |
Images with transparency are saved as WebP in automatic mode, because JPG would turn the transparent areas white. For a logo that must stay a PNG, use the image converter instead.
Frequently asked questions
How do I compress an image to 100 KB?
Choose 100 KB as the target and drop the image in. The tool lowers the quality, and the dimensions if needed, until the file is under 100 KB.
Will compressing make my photo blurry?
Usually not at quality 75 and above. Very small targets for large photos need resizing, which softens fine detail, so aim for the largest size the site allows.
Why did my PNG get converted?
PNG is lossless and can't be made much smaller by lowering quality. Saving it as JPG or WebP is what makes the big difference.
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