twineconvert

free · in-browser · no upload

AVIF to WebP
Converter

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

AVIF
to
WEBP

Select your file here to get started

or drop your file here.

Accepts .avif

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 AVIF 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.

Formats involved

About AVIF and WebP

AVIF, AV1 Image File Format

AVIF uses AV1 video codec compression for still images, typically 30-50% smaller than JPG and 20% smaller than WebP at the same visual quality. Supported in Chrome since 2020, Firefox since 2021, Safari since 16.4 (2023). The encoding step is significantly slower than JPG, which is why CDNs adopt it slowly. Best fit: hero images and photo galleries on modern sites where bandwidth matters.

How to open

All current browsers (2024+) display AVIF inline. Native OS viewer support varies, Windows 11 supports it natively, macOS only since Ventura. Older photo editors may need a plugin.

Full AVIF 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 AVIF to other formats

How we compare

AVIF → WebP vs the alternatives

FeatureUstwineconvertCloudConvertiLovePDFFreeConvertSmallpdf
Files uploaded to a server
Free file size limitNo limit1 GB200 MB1 GB5 GB
Free conversions per dayUnlimited10/dayLimitedLimited2/day
Signup required
Watermark on output
Works offline (after first load)

Last verified May 2026 from each competitor's pricing and FAQ pages. Limits and pricing change frequently.

FAQ

Common questions

Is this AVIF → 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 AVIF to WebP?

Modern web images where every kilobyte matters. Modern web imagery where smaller files load faster. The most common reason to convert is compatibility, WebP works in places where AVIF doesn't, or vice versa.

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

All current browsers (2024+) display AVIF inline. Native OS viewer support varies, Windows 11 supports it natively, macOS only since Ventura. Older photo editors may need a plugin.

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.