Image SEO on Wix: what's automatic and what's up to you

Wix handles most of the technical side of image SEO for you. When you upload an image, Wix compresses it, converts it to a modern format (AVIF, according to the Wix Help Center), resizes it for the visitor's device and lazy-loads it. You can't switch these off, and you don't need to configure them.

That leaves a short list of things only you can do: upload a good source file, write alt text that describes each image, put images on pages where they're relevant, and avoid the few file types Wix doesn't optimize. Alt text is the big one. It's the main way search engines and screen readers understand what an image shows, and Wix can't write an accurate description of your work without you.

This guide explains what Wix does automatically, what it leaves to you, and where the platform's limits are, including the fact that you can't control image file names in URLs.

What Wix does to your images automatically

Four things happen to an image between your upload and a visitor's screen.

Format conversion. The Wix Help Center states: "When you upload an image to your site, it is automatically converted to AVIF format." AVIF is a newer image format that produces much smaller files than JPEG at similar quality. Wix says AVIF is about 50% smaller than WebP, and its SEO hub says an AVIF file can be up to 80% smaller than a standard JPEG. The same hub says Wix serves AVIF whenever a visitor's browser supports it. You'll still see WebP mentioned on some Wix marketing pages. The Help Center is the more current source, and either way the conversion is automatic.

Compression and resizing. Images smaller than 25MB are automatically compressed, and Wix resizes images to balance quality and load time.

Device-aware delivery. Wix describes its infrastructure as serving the most optimal version of an image based on the visitor's device, screen resolution and browser capabilities. A phone doesn't download the same file as a large desktop monitor.

Lazy loading. Images further down the page load only as the visitor scrolls toward them. Wix shows a low-resolution placeholder first, then swaps in the full image. Lazy loading is on by default and can't be disabled.

Wix also converts uploaded images to the sRGB color space. If your photographer delivers files in another color profile, colors can shift slightly on the live site, so check key brand images after upload. The details are in Wix's article on optimizing your media.

What to upload: size, format and limits

Because Wix resizes downward, the rule is to give it a large, clean source and let it do the rest. Wix recommends uploading images of at least 2560 x 1440 pixels. A small image stretched across a wide section looks soft, and no optimization fixes that.

Wix accepts a long list of image types: JPG, JPEG, JPE, JFIF, PNG, GIF, BMP, HEIC, HEIF, TIFF, TIF, WEBP, AVIF, JPEG 2000 and RAW. Animated WEBP files are converted to a static image. The current list is in Wix's reference on supported media file types and file sizes.

Practical guidance that follows from those limits:

• Stay under 25MB per image. Wix's pages disagree about larger files. The file-size reference lists a 50MB limit, the performance best-practices page says images over 25MB can't be uploaded, and the SEO hub says images over 25MB aren't compressed. Under 25MB they all agree, so export from your photo software at a sensible size first.
• Use JPG for photos and PNG for graphics that need transparency. Wix converts both for delivery, so choose the format that preserves your source best.
• Use SVG for logos and icons where you have a vector file. It stays sharp at any size.
• Treat GIFs as a cost. They aren't auto-compressed, and animated GIFs are often several megabytes. Use them sparingly, or use a short video instead.

If your site carries a lot of large media files, check how your plan's storage allowance works in Wix storage and bandwidth limits.

Alt text: the part that's up to you

Alt text (alternative text) is a short written description attached to an image. Screen readers read it aloud to visitors who can't see the image, browsers show it if the image fails to load, and search engines use it to understand the image's subject. It's both an accessibility requirement and an SEO signal, and it's the one image setting where your input can't be automated away.

How to add alt text to a single image

1. Select the image in the editor.
2. Click the Settings icon.
3. Type a description in the field labeled What's in the image?
4. Publish.

How to write it

• Describe what's in the image, specifically. "Technician replacing a rooftop air conditioning unit" tells a reader something. "HVAC" does not.
• Keep it to a sentence or less.
• Include a keyword only where it fits naturally. A list of keywords isn't a description.
• Don't use the file name. Wix specifically advises against alt text like "bread.jpg".
• Skip "image of" or "picture of." Screen readers already announce that it's an image.

Galleries

Gallery images work a little differently. In Wix galleries, alt text comes from the image's title and description. In the Pro Gallery, if you haven't set alt text for an image, Wix falls back to its Title and then its Description. So an image titled "IMG_4032" ends up with that as its description. When you add images to a gallery, give each one a real title at minimum.

Finding images with missing alt text

Two built-in tools help. The SEO Setup Checklist flags missing alt text, including on images hidden behind other elements, which explains why it sometimes reports an image you can't see on the page. And the Accessibility Wizard scans the site and lists what's missing:

1. In the editor, open Settings and choose Accessibility Wizard.
2. Run the scan.
3. Open the Alt Text results and fill in descriptions.

Wix's SEO hub describes an AI alt-text generator inside the wizard. It can save time on a large image library, but read every suggestion. An AI can tell there's a person in a kitchen. It can't tell that the person is your head chef or that the dish is your signature item. For the wider accessibility picture, see our guide to Wix accessibility and ADA.

File names and image URLs

General SEO advice says to give images descriptive file names. On Wix that advice has limited reach, and it's better to know that than to spend an afternoon renaming files.

Wix's documentation is clear on the facts: "The name of your file does not appear in the URL." Wix assigns each media file an ID, serves it from its own media servers, and doesn't allow media URLs to be edited. The same applies to Pro Gallery images, whose URLs are generated automatically and can't be changed.

Wix doesn't say whether the original file name is used anywhere else that affects search. So keep your expectations modest. Descriptive file names are still worth using for a practical reason, which is that they make images easy to find in the Media Manager, but put your SEO effort into alt text, the surrounding page content and captions.

How images reach search engines

Three mechanisms on Wix help search engines discover and understand your images, and all three are automatic.

The sitemap. Wix includes image entries in the sitemap for main pages, Wix Stores, Wix Events, Wix Blog, Online Programs, Wix Restaurants and Portfolio. You don't build an image sitemap yourself. More on this in Wix sitemap and robots.txt.

Structured data. Structured data is code that labels the parts of a page for search engines. On product pages, booking services and CMS dynamic item pages, Wix's preset markup includes each image's URL, height, width and alt text. That's another place your alt text gets used, and another reason to write it. We explain the presets in Wix schema markup.

Page context. An image sits on a page with a title, headings and text. Search engines read all of that to judge what an image is about. A product photo on a page with a clear product name and description needs less help than an unlabeled image on a page with no text.

Social share images

The image that appears when someone shares your page on social media or in a messaging app is set separately, through a tag called og:image. On Wix, og:image is empty by default unless you set a site-wide social image. Two exceptions fill themselves in: product pages use the product image, and CMS dynamic item pages use the collection's primary image.

So for regular pages, set a social share image, or shared links may appear with no picture or one the platform chose for you. The setting is in the Social share tab of each page's SEO panel, and site-wide defaults are covered in Wix SEO settings: titles, descriptions and defaults.

Multilingual sites

If you use Wix Multilingual, image alt text can be localized per language. Switch to the secondary language in the editor, select the image, open Settings and fill in "What's in the image?" in that language. It's easy to forget, because the image itself doesn't change.

What Wix can't optimize

• Images over 25MB. Depending on which Wix page you read, they either can't be uploaded or upload without being compressed.
• GIFs. They aren't auto-compressed.
• Embedded videos. YouTube and Vimeo embeds load through iframes and, in Wix's words, "cannot be optimized by Wix."
• Too many images on one page. Lazy loading helps, but a page with a hundred large gallery images still asks a lot of a phone.
• Images with text baked in. Search engines and screen readers can't read words inside a picture reliably. Put important text on the page as real text.

The image that matters most for speed is the first large one a visitor sees, usually the hero image at the top of the page. If your pages feel slow, start there. Our guides to Wix site speed and Core Web Vitals and why your Wix site is slow go through diagnosis step by step.

A short image checklist

1. Export photos at 2560 x 1440 pixels or larger, and under 25MB.
2. Give files a descriptive name so you can find them later.
3. Upload, place the image and write alt text right away.
4. Give every gallery image a real title.
5. Set a social share image for key pages.
6. Replace heavy GIFs.
7. Run the Accessibility Wizard before launch and after large content updates.

Conclusion

On Wix, image performance is mostly automatic: conversion to a modern format, compression, resizing by device and lazy loading all happen without settings. Your part is the source file and the words. Upload large, clean images under 25MB, write specific alt text, title your gallery images, and don't expect file names to carry SEO weight when they never appear in the URL. If you'd like a review of your site's images and accessibility, eSEOspace offers an accessibility audit alongside our Wix work. More guides are in our Wix hub.

Frequently asked questions