Compress an image to a file size, not a quality
Upload forms rarely ask for a quality level. They say "photo under 100 KB" or "max file size 2 MB" and reject anything larger. A normal image compressor makes you guess: move the slider, check the size, try again. This tool turns it around. You type the limit, and it finds the highest JPEG or WebP quality that stays under it, for every image on its own.
- Exact limits: any target from 2 KB up, in KB or MB, plus one-click presets for 20, 50, 100, 200 and 500 KB and 1 MB.
- Quality first: the pixel size is kept whenever a sensible quality fits. Only when it does not, the picture is scaled down as little as possible.
- Batches: drop a whole folder of photos and download them as a ZIP, each one just under the limit.
What happens to your photo
Each image is drawn on a canvas in your browser and encoded at a high quality. If that file is already under the target, you get it right away. If not, the tool encodes it again at lower quality settings and halves the search range each time, which takes about eight tries. When even a quality of 50 is still too big, it looks for the largest pixel size that fits at a quality of 75 and then uses any room left to raise the quality again. Re-encoding also strips EXIF data such as the camera model and GPS position.
Some targets come up so often that they have their own page with tips for that size: 20 KB, 50 KB, 100 KB, 200 KB, 500 KB and 1 MB.
If a form also sets the pixel size, resize or crop first with the image resizer or the image cropper, then compress. To shrink by quality without a fixed limit, the image compressor is faster.
How to reduce a photo under a size limit
- 1Type the target size the form allows, or tap one of the common sizes.
- 2Choose JPG for upload forms or WebP for websites, then drop your images.
- 3Check the new sizes and pixel dimensions, and download each file or all of them as a ZIP.
Frequently asked questions
Are my images uploaded?
No. Every image is decoded, compressed and measured by your own browser. The files never leave your device, which also means there is no waiting for uploads.
How does it hit the size so precisely?
It encodes the image, measures the real file size, and adjusts. First it checks the highest quality, then it narrows down the best quality that still fits in a few steps. Only if even a low quality is too large does it scale the picture down and search again.
Why is my result a few KB below the target?
The tool counts 1 KB as 1,000 bytes and stops at the highest quality step that fits. A form that counts 1 KB as 1,024 bytes will see an even smaller number, so the file passes either way.
Can I keep PNG?
No, PNG has no quality setting, so it cannot be tuned to a size. The result is a JPG or a WebP. Transparent parts of a PNG turn white in JPG and stay transparent in WebP.
What if the target is too small?
You get the smallest file the tool could make, marked as Target too small, and a hint to raise the target. Very small targets like 5 KB only work for tiny images or simple graphics.