A lot of site owners ask me whether they need a special “image sitemap” for Google. Some have read that it is required for Google Images. Others have an SEO plugin that already makes one and have no idea what it does. A few have spent hours adding captions and titles inside their sitemap, not knowing Google stopped reading those tags years ago.
Let me clear this up in plain words. An image sitemap is useful for some sites and pointless for others. The deciding question is simple: can Google find your images on its own? If it can, an image sitemap adds very little. If it can’t, an image sitemap can be the thing that gets those images seen at all.
In this guide I will explain what an image sitemap is, how to tell whether you need one, which tags still matter, how to add images to the sitemap you already have, what to do about CDN-hosted images, and how to check whether your images are actually indexed.
What an image sitemap is, in plain words
A normal XML sitemap is a file that lists the pages on your site, so search engines know they exist. If you need a refresher, our lesson on XML sitemaps for beginners explains the basics, and our full guide to creating and submitting XML sitemaps goes deeper.
An image sitemap is the same idea for images. It is an extension to the sitemap format that lets you list, under each page, the images that appear on it. Google describes it simply:
“Image sitemaps are a way of telling Google about other images on your site.”
— Google Search Central, Image sitemaps
Note the word “other.” Google already finds most images by crawling your pages and reading the normal <img> tags. The image sitemap is for the images it might miss. Google’s image SEO page says the same thing from a different angle:
“You can provide the URL of images we might not have otherwise discovered by submitting an image sitemap.”
— Google Search Central, Google image SEO best practices
You can create an image sitemap in two ways, and Google treats them as equally valid:
- Add image tags to your existing page sitemap, so each page lists its own images.
- Create a separate sitemap just for images, and submit it alongside your page sitemap.
Either way, it is a hint. It helps discovery. It does not force Google to index anything.
Do you actually need one? A quick decision check
Here is the table I use with clients. Find the row that matches how your images are added to your pages.
| Your situation | Can Google find the images by crawling? | Image sitemap value |
|---|---|---|
Blog or service site; images are normal <img src> tags in the HTML | Yes, easily | Low. Nice to have if your plugin adds it automatically. |
| Store with product galleries where extra images load only when a shopper clicks a thumbnail or arrow | Often only the first image | Medium to high for the extra gallery images |
| Site built with a JavaScript framework that inserts images after page load | Sometimes, if rendering works | High, especially while you fix rendering |
| Images shown as CSS backgrounds | No. Google doesn’t index CSS images. | Low. Fix the markup instead; a sitemap won’t make CSS images indexable. |
| Images hosted on a CDN or separate image domain | Yes, if the page uses normal img tags | Medium. Helps tie the images to your pages and site. |
| Photographers, stock libraries, recipe, real estate or travel sites where image search brings real traffic | Usually yes | Medium. Worth having as a safety net for large image sets. |
The CSS row deserves a warning. Google states it plainly: “Google doesn’t index CSS images” (Google Search Central). Listing a CSS background image in a sitemap does not change how it is shown on the page. If an image matters for search, put it in an <img> element. Our guide on SVG icons and background images covers when CSS images are fine and when they cost you.
And if your goal is more traffic from image search in general, a sitemap is a small part of that. Our guide on getting traffic from Google Images covers the bigger levers.
When Google struggles to find your images on its own
Let me be more specific about the cases where an image sitemap earns its place. These are the patterns I look for when reviewing a site:
- Click-to-load galleries. The page loads one main image, and the rest only load when someone clicks an arrow or thumbnail. Google does not click, so those extra images may never be seen.
- Lightboxes and pop-ups. The large version of an image is only requested when someone opens a lightbox.
- Infinite scroll and “load more” buttons. Portfolios and galleries that add images as you scroll.
- Lazy loading that hides the real URL. Some older scripts put the real image URL in a
data-srcattribute and swap it in only when the image enters the screen. - Client-side rendered apps, where the HTML is almost empty until JavaScript runs.
Google’s guidance on lazy loading explains why these patterns cause trouble: “Google Search does not interact with your page” (Google Search Central). If an image needs a scroll, click or swipe to appear, it may never be loaded for Google. Our guide on lazy loading and SEO explains the safe ways to lazy load.
The best fix is always to make images visible in the HTML. An image sitemap is the backup that helps while you fix it, or when a design truly can’t change.
The only two tags that still matter (and the four Google dropped)
This is where many guides online are out of date. In May 2022, Google announced on its Search Central blog that several sitemap extension tags were going away. The current image sitemap page lists only two tags as required, and lists four as deprecated.
| Tag | Status | What it does / what to use instead |
|---|---|---|
<image:image> | Required | Wraps the information about one image. Up to 1,000 per <url>. |
<image:loc> | Required | The image URL. Can be on another domain, such as a CDN. |
<image:caption> | Deprecated | Put a visible caption on the page instead. |
<image:title> | Deprecated | Use a descriptive file name and alt text on the page. |
<image:geo_location> | Deprecated | Mention the location in page text or captions where useful. |
<image:license> | Deprecated | Use IPTC photo metadata or structured data for image licenses. |
So if you see an old sitemap like this, the title and caption lines are dead weight:
<image:image>
<image:loc>https://www.example.com/images/hiking-boot-side.jpg</image:loc>
<image:title>Waterproof hiking boot</image:title>
<image:caption>Side view of our waterproof hiking boot</image:caption>
</image:image>They won’t break anything, but Google ignores them. The descriptive work should happen on the page itself: good file names, alt text and visible captions. Our guides to image captions and surrounding text and to product image alt text explain how to do that well. For licensing, Google now relies on image metadata through IPTC fields or structured data.
Here is what a correct, modern image sitemap entry looks like. The namespace line at the top is required, or the image tags won’t be understood:
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
xmlns:image="http://www.google.com/schemas/sitemap-image/1.1">
<url>
<loc>https://www.example.com/products/waterproof-hiking-boot/</loc>
<image:image>
<image:loc>https://www.example.com/images/hiking-boot-side.jpg</image:loc>
</image:image>
<image:image>
<image:loc>https://cdn.example.com/images/hiking-boot-sole.jpg</image:loc>
</image:image>
</url>
</urlset>Adding image entries to the sitemap you already have
If you already have a page sitemap, adding images to it is usually the cleanest option. Each image sits next to the page it belongs to. Here is the process step by step.
- Check what you have. Open your sitemap in a browser (often
/sitemap.xmlor/sitemap_index.xml). Search the file forimage:image. If you find it, your plugin or platform already adds images. You may be done. - Add the image namespace. In the opening
<urlset>tag, addxmlns:image="http://www.google.com/schemas/sitemap-image/1.1". - List the images for each page. Inside each
<url>, add one<image:image>block per image, each containing an<image:loc>. - Use full, absolute URLs. Google’s sitemap guide says to “use fully-qualified, absolute URLs in your sitemaps” (Build and submit a sitemap). That applies to image URLs too: include
https://and the domain. - List the final image URL. Use the same URL the page actually loads, not a redirect, and not an older size or version of the file.
- Prioritize the images that matter. Product photos, original diagrams and portfolio pieces. Skip logos, icons, spacer images and decorative graphics.
- Check robots.txt. Make sure your image folders and CDN are not blocked. A sitemap entry for a blocked image is wasted.
- Submit and reference it. Submit the sitemap in Search Console and add a
Sitemap:line to robots.txt.
Sitemap: https://www.example.com/sitemap_index.xmlA worked example of sitemap size
Let me run through a hypothetical store so you can see the limits in practice. Say you have 1,200 product pages, and each page has 6 gallery images.
- Image entries: 1,200 × 6 = 7,200
<image:image>blocks. - Each entry is roughly 120 characters, so the images add about 7,200 × 120 = 864,000 characters, or under 1MB.
- The page URLs themselves are 1,200, well under the limit of 50,000 URLs per sitemap file. Google’s documentation says: “All formats limit a single sitemap to 50MB (uncompressed) or 50,000 URLs.”
- Each product has 6 images, far below the 1,000 images allowed per page.
In this example, one sitemap file is plenty. Only very large catalogs, with tens of thousands of products, need to split their sitemaps, usually by product type, through a sitemap index file.
Images on a CDN or another domain
Many sites serve images from a content delivery network (CDN), which is a network of servers that delivers files from a location close to each visitor. Your page might be on www.example.com while the images load from cdn.example.com or a provider’s own domain. If you want the basics, our article on CDNs and SEO explains how they work.
Normal sitemaps only accept URLs from the same site. Image sitemaps are different:
“Unlike regular sitemaps, you can include URLs from other domains in the <image:loc> elements of the image sitemaps.”
— Google Search Central, Google image SEO best practices
So listing CDN image URLs is fine. Three practical points help it work well:
- Verify the CDN domain in Search Console if you can. Google says this lets it report crawl errors for that domain.
- Use your own subdomain for the CDN where possible, such as
cdn.yourdomain.comthrough a CNAME record. The Ahrefs image SEO guide makes this point: when people embed or link to your images, the links then point to your domain rather than the CDN provider’s, and you can switch providers later without changing every image URL. - Check the CDN’s robots.txt. Some CDNs ship a default robots.txt. Make sure it doesn’t block Googlebot from your image files.
SEO plugins vs hand-built image sitemaps
Most sites should not write sitemaps by hand. Here is how I think about the options:
| Option | Good for | Watch out for |
|---|---|---|
| SEO plugin (for example, Yoast on WordPress) | Most WordPress sites; images are added to page sitemaps automatically | Gallery images loaded by JavaScript may not be included; check the output |
| Built-in platform sitemap (Shopify, Wix, Squarespace and others) | Stores and small sites that don’t want to manage files | Limited control; check whether it lists all gallery images or just the main one |
| Custom script from your database | Large catalogs and custom-built or headless sites | Needs a developer and must update automatically when products change |
| Hand-written XML file | A small portfolio with a handful of image-heavy pages | Goes stale fast; easy to break with one typo |
Yoast’s developer documentation, for example, says an image entry “should be output for each image in / associated with a page” in its sitemaps (Yoast XML sitemaps specification). Whatever tool you use, the rule is the same: open the file and look. Pick one product page with five gallery images and check how many of those five appear in the sitemap. That one check tells you more than any plugin feature list.
If you run WordPress and want the full setup, our WordPress SEO guide walks through it.
How to check whether your images are actually indexed
Submitting a sitemap is the easy part. Knowing whether it worked is harder, because Search Console gives limited image data. Its Sitemaps report counts pages and videos, but for image URLs, Google says “the report doesn’t currently show any data for those types of URLs” (Search Console Help). And, as the same page reminds us:
“There is no guarantee that a page URL discovered in a sitemap has been or will be crawled or indexed by Google.”
— Search Console Help, Manage your sitemaps using the Sitemaps report
So you need indirect checks. Here is how I would do it:
- Check the sitemap status. In Search Console, open Sitemaps and make sure the status is “Success.” If it says “Has errors” or “Couldn’t fetch,” fix that first.
- Look at image search performance. Open the Performance report, click Search type, and choose Image. Then open the Pages tab. Pages that get impressions here have at least some images showing in Google Images.
- Compare against your important pages. If key product or portfolio pages get zero image impressions after a couple of months, their images may not be indexed, or may not be competitive.
- Search Google Images directly. Try a
site:yourdomain.comsearch in Google Images, adding a product name. It is a rough check, not a complete count. - Inspect the page. Use URL Inspection, test the live URL, and look at the rendered HTML. If the image URL is not there, Google can only learn about it from your sitemap.
I treat these checks as direction, not exact counts. Google does not publish a full list of your indexed images, so you are looking for patterns, such as whole sections with no image visibility at all.
Questions people ask about image sitemaps
Is an image sitemap required for Google Images?
No. Google finds most images by crawling your pages and reading normal img tags. An image sitemap is an extra hint that helps with images Google might not find on its own, such as those loaded by JavaScript.
Should I make a separate image sitemap or add images to my main sitemap?
Google treats both the same. Adding image entries to your existing page sitemap is usually simpler, because each image sits next to the page it appears on and you have one file to maintain.
Do I still need image:caption and image:title tags?
No. Google deprecated image:caption, image:title, image:geo_location and image:license in 2022. Only image:image and image:loc are still used. Put captions on the page itself and use image metadata or structured data for licensing.
How many images can I list for one page?
Up to 1,000 image:image entries per url element, according to Google’s documentation. The normal sitemap limits of 50,000 URLs and 50MB uncompressed per file still apply.
Will an image sitemap get my images indexed faster?
It can help Google discover them, but it doesn’t guarantee crawling or indexing. Google still decides whether each image is worth showing, based on the image, the page it sits on and whether it is allowed to crawl it.
Can I list images hosted on a CDN?
Yes. Image sitemaps can include image URLs from other domains. Google recommends verifying the CDN domain in Search Console too, so you can see crawl errors for it.
Your image sitemap plan for this week
Here is how I would spend an hour on this:
- Open your sitemap and search for
image:image. - Pick three image-heavy pages and compare their images with what the sitemap lists.
- Remove deprecated caption, title, license and geo tags from any custom sitemap.
- Move important images out of CSS backgrounds and click-to-load galleries where you can.
- Check Search Console’s image search performance for your key pages.
Image sitemaps are a small piece of a bigger picture. For the rest, read our full guide to image SEO. And if you’d like our team to review your sitemaps, crawlability and image setup, our SEO service covers it. You can request a free quote any time.
Further reading on image sitemap
- SVG, Icons and Background Images: What Google Can Index
- Should URLs Include Dates or Categories?
- Image Captions and Surrounding Text: The Overlooked Image Signal
Sources for this image sitemaps guide
- Google Search Central: Image sitemaps
- Google Search Central: Google image SEO best practices
- Google Search Central: Build and submit a sitemap
- Search Console Help: Sitemaps report
- Google Search Central Blog: Spring cleaning – some sitemap extension tags are going away (May 2022)
- Google Search Central: Fix lazy-loaded content
- Google Search Central: Image metadata in Google Images
- Yoast developer docs: XML sitemaps functional specification
- Ahrefs: Image SEO guide
