“The image is too heavy, could you make it smaller?” A common request — and it means three different things.
Smaller in dimensions, smaller on disk, or lower in quality. These look connected but are separate, and which one you move decides both the work and the result. Start without settling that and you will usually do it twice.
Work backwards from the purpose
It will not attach, or the upload is rejected
That is file size — but before dropping quality, look at the dimensions first. Phone photos are commonly around 4000px wide, where 1600px is plenty for anything viewed on a screen. Halving the dimensions leaves a quarter of the pixels, and the file falls accordingly.
This site’s image resizer takes several files at once and works to a long-edge target. Leaving “do not enlarge” on stops smaller images being stretched up to meet it.
The dimensions have to stay
When the slot is fixed, compression is the tool. Image and video compression picks a resolution and quality from where the file is going. Video works the same way.
It is going on a website
WebP holds much the same appearance at a smaller size than JPEG, and every current browser supports it. For anything web-facing it is the first choice. Changing format alone is a job for file conversion.
Common crossed wires
- “Increase the resolution” — this means dpi (printing) or pixels (dimensions) depending on who is asking. For print, what is needed is more pixels; rewriting the dpi of a small image changes nothing visible.
- “Send it in high quality” — nothing exceeds the original. If you were handed something already reduced, there is nothing to recover; ask for the camera file.
- A PNG that weighs a lot — photographs saved as PNG run several times larger than JPEG. PNG suits diagrams and screenshots; photographs want JPEG or WebP.
- Transparency disappeared — JPEG cannot store it. Keep the file as PNG or WebP when transparency matters.
In short: suspect the dimensions first, compress if that is not enough, and change format as the final nudge. In that order you spend the least quality getting there.
The stem separation in this article runs free in your browser — no sign-up, and your audio never leaves your device.