twineconvert

free · in-browser · no upload

PNG to WebP
Converter

Drop your PNG file. We'll convert it to WebP right here in your browser, your file never leaves your device.

or drop your file

Select your file here to get started

or drop your file here.

Accepts .png

nothing uploaded no file size cap no signup

How it works

Three steps. No upload, no signup.

  1. 1

    Drop your file

    Click the dropzone above or drag a PNG from your desktop. Files of any size, there's no upload, so there's no upload limit.

  2. 2

    Convert in your browser

    The conversion runs entirely in this tab using JavaScript and WebAssembly. Your file never touches our servers, we don't have any.

  3. 3

    Download

    Get your WebP the moment the conversion finishes. Convert another, or close the tab.

Files stay on your device

Your file is never uploaded. The entire conversion runs in your browser using WebAssembly. We can't see what you convert because we have no server to see it.

No file size limit

Server converters cap free users at 1-2 GB and gate larger files behind a paid plan. Since nothing uploads, our limit is whatever your browser can handle.

Free, no signup, no ads on conversions

No account required. No watermark on the output. No queue. Drop a file, get a converted file.

Why convert PNG → WebP

What this conversion is actually for

WebP compresses 25-35% smaller than PNG at the same visual quality and keeps the alpha channel. For anything going on the web, site assets, blog images, app icons, WebP is the modern default that Lighthouse and PageSpeed explicitly recommend. Smaller images = faster pages = better SEO and lower bandwidth bills.

A real example

Your Next.js site's hero image is a 1.4MB transparent PNG and Lighthouse is dinging your LCP. Convert to WebP here; it drops to ~400KB with identical visual quality and transparency intact. Swap the file, redeploy, LCP improves.

Troubleshooting

An older tool / email client won't open the WebP.

WebP has had universal browser support since 2020 (Safari was last, in Big Sur). But legacy desktop software, old Office versions, some email clients, Windows 7-era image viewers, predates it. If the recipient is on legacy software, keep PNG. WebP is for the web, not for emailing to your accountant.

Formats involved

About PNG and WebP

PNG, Portable Network Graphics

PNG is a lossless image format, the file size is larger than JPG, but every pixel is preserved exactly. It supports full transparency (alpha channel), which JPG cannot. Created in 1996 specifically as a patent-free replacement for GIF, PNG is the standard for screenshots, logos, icons, UI graphics, and any image that needs sharp text or transparent backgrounds.

How to open

Universal support, every OS, browser, and image editor reads PNG. macOS Preview, Windows Photos, and any web browser open PNGs without any conversion step.

Full PNG format guide →
WebP, Web Picture

WebP is Google's image format, designed in 2010 specifically for the web. It compresses 25-35% smaller than JPG at equivalent quality, supports transparency like PNG, and supports animation like GIF. Browser support is universal as of 2020 (Safari was the last holdout). The main reason most images aren't already WebP: legacy software (older Office versions, some email clients) doesn't open it.

How to open

All modern browsers display WebP natively. Photoshop added native support in version 23 (2021); earlier versions need a plugin. macOS Preview reads WebP since macOS Monterey. On Windows, the Photos app supports it; older viewers may not.

Full WebP format guide →

Related tools

Convert other files to WebP

Convert your PNG to other formats

FAQ

Common questions

Is this PNG → WebP converter really free?

Yes. No signup, no watermark, no daily file count limit. Every conversion runs in your browser, your file never touches our servers because there are no servers.

Where does my file go when I convert it?

Nowhere. The conversion runs entirely in your browser using JavaScript and WebAssembly. Your file is never uploaded to our servers. We don't have any servers handling files, there's nothing for us to log, store, or accidentally leak.

What's the maximum file size?

Whatever your browser can hold in memory. Practically, this means a few hundred MB on most computers, significantly larger than the 1-2 GB caps that server-upload converters charge for. Very large files (multi-GB) may require closing other browser tabs first.

Why convert PNG to WebP?

Screenshots, logos, UI graphics, and any image needing transparency. Modern web imagery where smaller files load faster. The most common reason to convert is compatibility, WebP works in places where PNG doesn't, or vice versa.

How do I open a PNG file in the first place?

Universal support, every OS, browser, and image editor reads PNG. macOS Preview, Windows Photos, and any web browser open PNGs without any conversion step.

Does this work offline?

Once the page is loaded, the conversion itself runs entirely offline. The first time you use a tool, your browser downloads the conversion library (a one-time cache). If you reload while offline, the page won't load, but you can install the site as a Progressive Web App for full offline use.

Can I convert multiple files at once?

Single file at a time for now. Batch conversion is on the roadmap, for now, drop one file, download the result, then convert the next.