image tool
Compress Image
Re-encode an image at a lower quality and compare the real file sizes. When re-encoding would make the file bigger, the original is returned and the result says so.
Add files
Drop JPEG images, PNG images, WebP images here, or choose files. Everything stays on this device.
Waiting for files
Accepted input
- JPEG, PNG and WebP images, up to 10 at a time
Limits
- Up to 20 MB per image and 10 images per batch.
- Up to 40 megapixels per image, checked before the pixels are allocated.
- No image is guaranteed to shrink: already optimised files can grow.
Local processing
- Files are read in your browser and are never uploaded to a server.
- Nothing is stored after you close or reload the page.
- Encoding happens on a canvas inside your browser tab.
How to use Compress Image
- Add one or more images with the drop zone or the file chooser.
- Pick the output format and a quality between 1 and 100.
- Press Compress images and read the before and after sizes before downloading.
What it does
- Shows the original size, the new size and the percentage saved for every file.
- Returns the original file when re-encoding would have made it larger.
- Keeps transparency for PNG and WebP; JPEG output is flattened onto white.
Limits and things to know
- Re-encoding always throws away the original compressed data, so quality is not restored later.
- Quality below about 60 shows visible artefacts around text and edges.
- Animated WebP and GIF are reduced to their first frame, and the result says which frames were dropped.
Example
Getting a screenshot under a 200 KB upload limit
Add a 1.4 MB PNG screenshot, choose JPEG at quality 75, and check the reported size. If the file is a UI screenshot with flat colours, WebP often does better; compare both before you commit to one.
Frequently asked questions
Will my image always get smaller?
No. An image that is already well optimised can come out larger. The tool compares the byte counts and hands back the original in that case instead of pretending it worked.
Does compressing a PNG work?
PNG is lossless, so a quality number does nothing to it. Choosing PNG re-encodes the file, and the tool tells you the size may not change at all.
What happens to an animated GIF?
Only the first frame is written to the result, and the note under the download lists which frames were dropped.
Runs entirely in your browser on ap98.com. Files are never uploaded.