Why did one of my PNGs come out bigger?

PNG is lossless and very good at flat colour, so a simple icon or a piece of line art is often already near-optimal, and re-encoding it adds WebP container overhead instead of saving bytes. The table flags anything that grew, and the keep-the-original toggle swaps those files back to PNG automatically. Photographs and screenshots with gradients in them almost always shrink.

Can I drop JPEGs in as well?

No. Anything that is not a PNG is refused, with a pointer to the JPG to WebP tool instead.

PNG to WebP

No upload · runs in your browser

Drop PNG images hereor click to browse. As many as you like, they stay on your deviceSelect PNGs No upload · processed locally · auto-deleted

Runs entirely in your browser, nothing is uploaded.

How it works

PNG to WebP: Alpha Kept, Every Saving Listed

Convert PNG to WebP with the alpha channel intact. Quality starts at 85%, and the table beside each file shows what the trade bought you.

What this does

Alpha transparency carries straight across into the WebP
A per-file table of what each image weighed before and after, with the percentage change
“Keep the original when WebP is larger” is on by default, so flat icons stay PNG
Quality slider from 50% to 100%, starting at 85%

FAQ

No. The encoder here is the one built into your browser’s canvas, and on that path every setting is lossy, 100 means as close as this encoder gets, not pixel-identical. The re-encode also drops what PNG carried alongside the pixels, so colour profiles and text chunks do not survive. Keep the PNG when you need an archival master. For images being shipped to a web page, 80 to 90 is invisible in practice and much smaller.

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