Why doesn't the quality slider work for PNG?

PNG is lossless — it has no quality setting to trade away. To make a PNG smaller you either reduce its dimensions or convert it to a more efficient format like WebP.

What's the best way to compress a PNG?

If the image is a photo, convert it to JPG or WebP. If it's a graphic with transparency, convert to WebP to keep transparency while shrinking the file. Resizing helps in all cases.

Will I lose transparency?

No, as long as you keep PNG or switch to WebP. Both support transparency. Converting to JPG would fill transparent areas with white.

Yes. Everything happens in your browser; nothing is uploaded.

Compress PNG — Shrink PNG File Size in Your Browser

Why PNGs are big — and how to fix it

PNG is lossless: it stores every pixel exactly, with no quality knob to turn. That's a strength for crisp graphics and transparency, but it's why PNGs balloon in size, especially for photographs. Because there's no quality setting, the two reliable ways to compress a PNG are different from JPG:

Resize it. File size scales with the number of pixels. Halving the width and height roughly quarters the pixel count. Set a Max width to the size the image is actually displayed at — this is usually the single biggest win.
Change the format. Re-encoding to WebP keeps transparency and is typically ~26% smaller losslessly, or far smaller if you allow lossy WebP. For photographic PNGs with no transparency, JPG is smaller still.

Keeping PNG but want it smaller?

Resizing is your only lever here, since this tool re-encodes (it doesn't run a PNG-specific optimiser). For the biggest reduction while keeping transparency, switch the format to WebP using the buttons above.

Choosing where to go

Graphic or logo with transparency → convert to WebP (keeps transparency, much smaller).
Photo, no transparency needed → convert to JPG (smallest for photos).
Must stay PNG → set a max width to reduce dimensions.

How to compress

Keep PNG and set a Max width, or click WebP / JPG to change format.
Drop your PNG files above.
Download individually or as a ZIP.

Biggest savings with transparency kept?

WebP is the best replacement for heavy PNGs on the web.

Convert PNG to WebP

More detail: resizing images for the web and JPG vs PNG vs WebP.

Frequently asked questions

Why doesn't the quality slider work for PNG?: PNG is lossless — it has no quality setting to trade away. To make a PNG smaller you either reduce its dimensions or convert it to a more efficient format like WebP.
What's the best way to compress a PNG?: If the image is a photo, convert it to JPG or WebP. If it's a graphic with transparency, convert to WebP to keep transparency while shrinking the file. Resizing helps in all cases.
Will I lose transparency?: No, as long as you keep PNG or switch to WebP. Both support transparency. Converting to JPG would fill transparent areas with white.
Is it private?: Yes. Everything happens in your browser; nothing is uploaded.