PNG is the format that stores sharp edges and see-through pixels. Logos, diagrams and interface captures belong in PNG. A holiday photograph usually does not: the file stays huge because PNG refuses to throw away detail unless you ask it to limit colors.
At quality 95 or above this tool writes a lossless PNG and then runs an optimizer. Below that, it builds a 256-color (or smaller) PNG so screenshots and flat graphics shrink. Photographs with gradients should move to JPEG, WebP or AVIF instead.
How to compress a PNG
Drop the PNG files
Logos and screenshots can share a batch. Watch the comparison view: a limited palette can band a photo even when a logo still looks perfect.
Decide on color count
Leave quality high for a logo. Lower it when the screenshot is mostly flat color and you need the file under a limit.
Confirm transparency
Checkerboard areas should stay empty, not turn white. Download the PNG and open it on a colored background if you are unsure.
What stays special about PNG
Transparency
JPEG cannot keep a cut-out logo. PNG can. That is the main reason to accept a larger file.
Text stays sharp
Screenshots of receipts, code and chats survive PNG better than JPEG, which rings around letters.
When to leave PNG
If the picture is a photograph, switch the output to WebP or JPEG. You will often save more than any PNG optimizer can, and the photo will look better than a 256-color version.
PNG settings that behave
| Picture | Quality | Why |
|---|---|---|
| Logo or icon | 95–100 | Lossless, transparency kept |
| Screenshot | 40–80 | Fewer colors, still readable text |
| Photograph | Switch format | PNG is the wrong container |
PNG compression questions
How do I compress PNG images without a white box behind the logo?
Keep the output set to PNG. The encoder stores transparency. JPEG and a flattened GIF will paint a background.
Why did my PNG get bigger?
A lossless recompress of an already-optimized PNG can add a few bytes. Lower the quality to allow a palette, or change format if the image is a photo.
Is PNG-8 good enough for a screenshot?
Often yes, when the screen is UI, text and a handful of colors. Photos and smooth gradients inside the shot will band. Compare before you download.
Do you upload the PNG to optimize it?
No. Palette reduction and the lossless optimizer run in your browser.