FreeNo uploadNo sign-upBatch
Compress PNG Images
Make PNG screenshots, logos and graphics much lighter while keeping transparent backgrounds.
Drop PNG images to compress
batch and mixed formats welcome
- Private by design. Converted inside your browser.
- Instant. No upload queue, no waiting.
- Unlimited. Convert hundreds of files, download as ZIP.
How to compress PNG images
Add your PNG images
Drop files on the tool, click Choose files or paste from the clipboard. Add as many as you like.
Set the quality
Move the quality slider. Lower means smaller files; the before and after sizes update instantly.
Download smaller files
Save each file or download everything as a ZIP. Files that cannot get smaller are returned unchanged.
Lighter PNGs that keep transparency
PNG is lossless, so screenshots and graphics saved as PNG are often several megabytes. Most of them use far fewer colours than PNG can store.
This tool converts each PNG to an optimised palette of up to 256 colours with full transparency, the same approach used by well-known PNG optimisers. Graphics and screenshots usually shrink by 50–80% and look the same.
Frequently asked questions
Is PNG compression lossless here?
Not exactly. Colours are reduced to an optimised palette, which is what makes the file small. For most graphics the change is invisible.
Does it keep the transparent background?
Yes. The palette includes transparency, so cut-outs and soft edges stay as they were.
Why is my PNG not smaller?
Some PNGs are already optimised. If the result would be larger, you get the original back.
Can I use the compressed PNG on my website?
Yes. It is a standard PNG file that every browser and editor opens.
Are my files uploaded to a server?
No. formatmath converts files with code that runs inside your browser. Your files are never uploaded, stored or seen by us.
Is it free?
Yes. There is no watermark and no daily limit. An account is optional and only keeps a history of your conversions.