Email limits, upload caps, slow pages — oversized images cause real friction. This compressor re-encodes your image at the quality you choose, optionally capping its dimensions, and reports the honest result: exact bytes before and after, measured on your actual file. If a file can't get smaller, it tells you that instead of dressing up a bigger file as a win.
Where image weight actually lives
Two things decide a photo's file size: how many pixels it has, and how hard the encoder works to describe them (the quality setting). Quality 80% typically cuts a camera JPG to a third or less of its size with no visible change on screen — camera files are written to be edited, not emailed. Dropping dimensions helps even more: a 4000 px photo shown at 1200 px is carrying about ten times the data it needs.
Format honesty
JPG and WebP compress photographs well because they may discard invisible detail. PNG is lossless — brilliant for graphics, stubborn for photos: a “compressed” PNG photo barely moves, and this tool will show you that plainly in the results. Screenshots and logos: use PNG or WebP. Photos: JPG at 75–85%, or WebP for the smallest file of all.
Worked example
Use the sample photo (a PNG, 127 KB). Switch the output format to JPG and press Compress at the default 80% quality: the sample comes back at about 30 KB — roughly 76% smaller. But leave the format on “Keep original” and the same file does not shrink at all (127 KB in, 127 KB out in testing): PNG is lossless, so re-saving a PNG cannot squeeze it — for a PNG photo, changing format is the compression. Then slide quality to 40% and again to 95% and watch the JPG size follow. That slider is the whole trade-off between fidelity and bytes, made visible.
How to use this tool
- Drop your image onto the box (or use the sample photo).
- Set quality — 80% is the sweet spot for photos.
- Optionally cap the max dimension if the image will only be shown small.
- Press Compress image and read the true before/after sizes.
- Download the compressed copy; your original is untouched.
Chasing a specific limit?
For “must be under 200 KB” forms: start at 80% with no dimension cap. Still over? Add the 1280 px cap before dropping quality below 60% — smaller dimensions hurt less than starved quality. Still over? 800 px and 60% will fit almost any photo under almost any limit.