Free PNG to WebP Converter

How PNG to WebP conversion works

The browser reads the selected PNG, decodes it to raw pixels, and hands those pixels to its own WebP encoder; the resulting file is offered back as a download in this tab, with no server-side upload endpoint in the processing path.

Because the PNG source is lossless, the browser's WebP encoder is working from full-fidelity pixel data with nothing already discarded — unlike converting from a JPG or WebP source. Output size and encoder speed still vary between Chrome, Firefox, Safari, and Edge, and unusual PNG variants (16-bit color, interlaced PNGs) can decode slightly differently across browsers.

Start with the tools index to browse other conversions, or read how local browser processing works before converting files you consider sensitive.

PNG and WebP compatibility

PNG is a lossless format supported by essentially all browsers, image editors, and operating systems, and the file always decodes to the exact pixels that were encoded. WebP is supported in current versions of Chrome, Edge, Firefox, and Safari, but some older devices, email clients, and print or desktop-publishing workflows still expect PNG or JPEG. Before replacing PNG assets in a production system, confirm that every consumer of the file, including CDNs and older mobile apps, can decode WebP.

See the WebP vs PNG comparison guide for a size and transparency breakdown. The main converter's image format guide also covers GIF, SVG, JPEG, and BMP.

Choosing quality for PNG to WebP

PNG is lossless: the source file already holds the complete pixel data with no compression artifacts. This tool's WebP export uses the browser's Canvas image encoder, which is lossy in current browsers even at the "Original" preset — the Canvas API does not expose a lossless WebP encoding mode. Converting PNG to WebP with this tool is therefore always a lossy step, so the real decision is whether that quality tradeoff is acceptable for a given image.

High (0.9) keeps loss difficult to notice on photographic PNGs such as scans or screenshots that include photos. Recommended (0.75) and Compact (0.5) can introduce visible banding on flat-color PNGs such as icons, logos, and UI screenshots with sharp edges or text — check the output before replacing a logo asset. The alpha channel carries over correctly in the WebP output; only conversion to JPEG flattens transparency.

If a project needs byte-for-byte lossless WebP output, use a dedicated lossless WebP encoder outside the browser; this tool's export path cannot produce that result.

Batching PNG to WebP conversions

PNG file size varies widely: a flat-color icon can be a few kilobytes, while an uncompressed or high-resolution PNG exported from a design tool can reach tens of megabytes. Once decoded in the browser, a 12-megapixel image occupies roughly 48 MB of memory (width times height times 4 bytes per pixel) regardless of the file's size on disk, so decode memory — not the PNG's stored size — is the real limit on batch size.

Start with about 50 files per batch on a desktop browser and 10 to 20 on mobile, then use the ZIP download once the batch finishes instead of saving files one at a time.

What is PNG?

PNG (Portable Network Graphics) is a lossless format that supports transparency and is ideal for graphics, logos, and screenshots.

What is WebP?

WebP reduces image file sizes while preserving quality. It supports both lossy and lossless compression and transparency.

Deep Dive: Read our full PNG vs WebP comparison guide.

Frequently Asked Questions

Is the conversion local?

Yes. The conversion uses browser-native image processing. File contents are not intentionally uploaded by this tool.

Can I convert multiple PNG files at once?

Yes, you can drag and drop hundreds of PNG files and convert them all to WebP in one click.

What is the limit?

There is no account-level file count limit. Practical limits depend on your device memory and browser capability.

Which version should I use for sensitive files?

Privacy

Privacy build: This build removes ads, analytics, remote fonts, runtime CDN scripts, and file-operation telemetry. Selected files are processed in the browser using local JavaScript and browser APIs.

Selected images. ConvertUnlimited converts images entirely inside your browser. Selected file contents are processed locally in your browser for this supported workflow. ConvertUnlimited does not provide a server-side upload endpoint for this processing flow. File contents are not intentionally uploaded by this tool.

Contact. For privacy questions, reach out via the project's GitHub.