Introduction
You download an image from a website on your Mac, double-click it, and Preview either throws an error or shows a blank window. The file ends in .avif or .webp, and your Mac does not know what to do with it. Both formats are becoming the default for web images, but macOS support is still patchy depending on your version. You can see the image fine in Safari, but the moment you try to open it in Preview, Quick Look, or Photos, you hit a wall. The good news is you do not need to install third-party software to view and convert these files. In this guide we cover how to open AVIF and WebP images on a Mac using built-in tools and browser-based converters, with no downloads required. We also explain which format to convert to depending on whether you want to view, edit, or archive the file.
Why This Happens
Apple has been slow to add native AVIF and WebP support to macOS. Preview gained WebP support in macOS Big Sur (11) and later, but AVIF support is still limited even in recent macOS versions, with Quick Look often failing to generate thumbnails for AVIF files. Safari can display both formats on web pages, but that does not help when you have a downloaded file you want to open or edit. The underlying issue is that AVIF is a very new format based on the AV1 video codec, and Apple has not shipped a system-wide decoder that all apps can use. WebP is better supported but still trips up older Macs and some third-party image apps. The result is a frustrating gap between what Safari can display and what Preview, Quick Look, and Photos can open, and that gap is what sends Mac users searching for a fix.
3 Solutions
Solution 1: Open AVIF and WebP in Safari or Chrome. Drag the file into a browser window. Safari and Chrome both render AVIF and WebP instantly, no install required. This is perfect for a quick look, but it does not help if you need to edit the file or import it into Photos.
Solution 2: Convert AVIF to PNG in your browser. Run your AVIF files through a piczen AVIF to PNG converter, then open the PNG in Preview. This gives you universal Mac compatibility and a file you can edit, share, or archive.
Solution 3: Convert WebP to JPG for editing. For WebP files you need to edit, use a webp converter to get a JPG that opens in Preview, Photos, and every Mac image app. JPG is ideal for photos where file size matters.
Step-by-Step Guide
For the quickest view, open the file in a browser. Open Safari or Chrome, then drag your AVIF or WebP file straight into the browser window. The image renders instantly, no setup required. This is perfect for a quick look, but it does not help if you need to edit the file or import it into Photos. For editing, convert first. Open a new tab and load the avif to png converter if you have AVIF files, or the webp to jpg converter if you have WebP files. Drag your file onto the page. The tool processes it in a few seconds. Click Download to save the converted file to your Mac. Double-click the new PNG or JPG and it opens in Preview with no errors. From there you can edit, import to Photos, or drop it into any app that rejected the original AVIF or WebP. For batches, drag multiple files onto the converter at once and download a zip. Extract it with a double-click and you have a folder of Mac-friendly images.
Pros and Cons
Opening AVIF and WebP in a browser is the fastest peek with zero setup, but it offers no editing or sharing path. Converting to PNG or JPG is the universal fix because both formats open in every Mac app, from Preview to Photos to third-party editors. The tradeoff is a quick conversion step before you can work with the file. Installing third-party viewers like ImageGlass or AVIF codecs is an option, but it adds software to your Mac and only helps on that one machine. For most Mac users, the practical answer is to keep a browser converter bookmarked. AVIF and WebP downloads are only going to get more common as the web shifts to these formats, so building a one-click conversion into your workflow is the cleanest way to handle them without installing anything. The converted files slide right into your existing Mac image workflow. As AVIF adoption grows, expect to see more of these files landing in your downloads folder, especially from news sites and image-heavy platforms that have switched to the format for its superior compression. The same browser-converter approach handles AVIF today just as well as it handles WebP, so you are future-proofed either way. Keeping one converter bookmarked covers both formats and saves you from hunting for a fix every time a new file type shows up.