Convert PNG to WebP
100% private — runs on your device, never uploaded. Works offline once loaded.
Convert PNG images into the modern WebP format to dramatically reduce file size while keeping transparency. Everything happens locally in your browser.
PNG was built for graphics, not photos — and it shows in file size
PNG compresses images losslessly using the DEFLATE algorithm (the same family of compression as ZIP files), which works by finding repeated patterns of pixels. That makes it excellent for screenshots, app icons, logos, and diagrams full of flat colors and sharp edges, but it means PNGs of anything with lots of subtle color variation — a photo with a transparent cutout, a gradient-heavy illustration — end up much larger than they need to be.
Converting those PNGs to WebP keeps the same alpha-channel transparency but re-encodes the image using WebP's more modern prediction and entropy-coding techniques, which routinely cut file size by half or more, especially on PNGs that contain gradients, shadows, or soft-edged transparency that DEFLATE handles poorly.
Two flavors of WebP, one transparent result either way
WebP actually supports both a lossless mode (pixel-for-pixel identical to the source, like PNG) and a lossy mode (smaller, with imperceptible quality loss on most images). Either way, the alpha channel — the part of a PNG that makes backgrounds transparent — carries over intact, so a logo or icon with a see-through background stays see-through after conversion.
Where the savings matter most
Sites with heavy UI chrome feel this the most: a documentation site full of annotated screenshots, an e-commerce theme with dozens of icon and badge PNGs, or a marketing page with a transparent-background logo repeated in the header and footer. Multiply a 200KB PNG screenshot by fifty pages of documentation and the WebP savings become a real bandwidth and hosting-cost difference, not just a rounding error.
One place WebP won't help much: a simple 16-color icon already saved as an 8-bit palette PNG is often near its practical size floor, since DEFLATE handles small, repetitive palettes efficiently already.
A practical habit
Keep your original PNG as the editable master — especially for logos and screenshots you might crop or annotate again later — and generate the WebP copy only for the version you actually publish. If you ever need to go back the other way, converting WebP to PNG is just as quick.
Frequently asked questions
Does WebP keep transparency?
Yes — WebP supports transparency like PNG, but usually at a much smaller file size.
Are my images uploaded?
No — everything runs in your browser and your files never leave your device.
Does the transparent background survive the conversion?
Yes, WebP has full alpha-channel support, so any transparent or semi-transparent areas in your PNG remain transparent in the output.
How many files can I convert at once?
You can drop in multiple PNGs together and each one is converted to its own WebP file.
Will an already-tiny icon PNG shrink much further?
Not necessarily — small palette-based PNGs (few flat colors, no gradients) are often already near-optimal, so the size reduction there is smaller than for photo-like or gradient-heavy PNGs.
Is the conversion lossless or lossy?
WebP supports both modes; for typical web-delivery use this tool favors settings that keep visual quality high while still meaningfully reducing file size.
What about animated PNGs (APNG)?
Standard single-frame PNGs are what this tool is built for; animated PNG sequences are a less common format and may not convert as expected — WebP does support its own animation format separately.
Should I delete my original PNGs after converting?
It's worth keeping the PNG as your source file, particularly for logos or graphics you might need to re-edit later, since PNG is easier for most image editors to open and modify.
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