toolkit Drop as many PNG files as you like above to shrink them right here, in this browser tab, with the batch handed back as one .zip. Nothing is uploaded — which is the whole difference between this and the hosted PNG optimisers, since site assets are routinely under an NDA or simply not public yet. This isn't a lossless re-save: the colour palette is reduced too, the same trade pngquant and TinyPNG make.
What this page actually does to your PNG
The image is quantized down to a palette of at most 256 colors, chosen and dithered to look as close to the original as the eye can tell at normal viewing size, then losslessly re-compressed on top of that. Pixels change — this page fixes that setting rather than exposing a slider, so there's no way to ask it not to.
Shrink a whole folder of PNGs
This is usually an asset-pipeline job rather than a single-image one: every icon, screenshot or export in a directory, all needing the same treatment. Select the lot and each is quantized and re-compressed in turn, then offered as one .zip with the original file names intact, ready to drop straight back into a project. Free-tier limits are the usual obstacle elsewhere — TinyPNG's own web page meters you by the month. Here the compression runs on your machine, so there is nothing to count.
When this is the right tool
Screenshots, icons, flat illustrations and other PNGs with a small number of distinct colors shrink dramatically this way, often 50–80%, because that content was already close to 256 colors before quantizing. A photographic PNG with millions of distinct colors will show more visible change for the same size win — for those, converting to JPEG or WebP usually beats staying in PNG at all, unless you specifically need transparency.
Transparency survives
Each palette entry keeps its own alpha value, so translucent and fully transparent areas are preserved — this is a color-count reduction, not a flatten-to-opaque step.
Want a lossless result instead?
This page is fixed to the lossy preset on purpose — that's the whole point of it. The PNG optimizer on the main converter page offers a lossless option too, which re-compresses without changing a single pixel, if that's what you actually need.
Frequently asked questions
Is my image uploaded anywhere?
No. Everything happens locally in your browser via WebAssembly; the file never leaves your device.
Can I compress many PNG files at once?
Yes, with no monthly quota or per-batch cap of any kind. Add a whole folder; each file is shrunk in turn and the results come back as a single .zip with their original names, so they can go straight back where they came from.
Will this change how my PNG looks?
Yes, slightly — colors are reduced to a palette of at most 256 and dithered to compensate. For flat-color images like screenshots and icons the difference is usually not visible at normal size; for photographic PNGs it's more noticeable.
Does transparency survive?
Yes — alpha is kept per palette entry, so translucency and fully transparent areas are preserved.
Can I turn off the color reduction on this page?
No, not here — this page exists specifically to apply it. The homepage's PNG optimizer has a lossless option if you want to compare against a result with no pixels changed.
How much smaller will my file get?
It depends heavily on the image — flat-color PNGs (screenshots, icons, simple illustrations) commonly shrink 50–80%; complex photographic PNGs shrink less.