Duplicate content has become an unavoidable issue for many eCommerce websites. Product pages, category pages, homepage, checkout pages and more end up having very similar or identical content across them. This duplicate content can confuse search engines about which pages to index and rank for target keywords.
Canonical tags allow eCommerce sites to indicate the “master” page that search engines should prioritize, avoiding dilution of page authority and optimization signals.
In this article, we’ll cover:
- What are canonical tags, and how they work
- Common duplicate content issues in eCommerce
- When to use canonical tags for technical eCommerce SEO
- Implementing canonical tags correctly
- Tracking success with Google Search Console
- Additional tips for managing duplicate content
Key takeaways
- Canonical tags indicate to search engines which URL is the authoritative version of a page.
- Common eCommerce duplicates include HTTP vs HTTPS, www vs non-www, query parameters, pagination, and international URLs.
- Point all duplicate page versions to the single canonical URL you want indexed through proper link tag implementation.
- Monitor index status, rankings, impressions and clicks for canonical vs duplicate URLs in Google Search Console.
- Avoid referencing multiple canonicals. Use a single canonical URL per page to prevent signal dilution.
- Create unique titles, meta descriptions, and content where possible to further differentiate pages.
- Implementing a comprehensive canonicalization strategy helps eCommerce sites improve discoverability, crawl efficiency, and rankings.
What are canonical tags and how do they work?
A canonical tag is an HTML <link/> tag that goes in the <head> section of webpages. It indicates the “canonical” or “preferred” URL that search engines should index and rank for the content on that page.
For example:
<link rel=”canonical” href=”https://www.example.com/product-page” />
This tells search engines that https://www.example.com/product-page is the canonical URL, even if the content exists on other URLs like:
- https://example.com/product-page
- https://www.example.com/product-page?color=blue
When Google sees the canonical tag, it will consolidate the link equity and optimization signals for the page to the canonical URL. This avoids spreading authority thinly across duplicate versions.
The canonical URL should point to the most authoritative version of the page with the strongest optimization – generally, the page with the strongest link profile.
Common duplicate content issues in eCommerce
Here are some common ways that duplicate content emerges for eCommerce sites:
- HTTP vs HTTPS – Having product and category pages on both HTTP and HTTPS can dilute authority.
- WWW vs non-WWW – Accessing site pages with and without the www subdomain creates duplication.
- Query Parameters – URLs with query strings like ?sort=price can duplicate pages.
- Pagination – Breaking up product category pages across multiple pages creates duplicate content issues.
- International URLs – Having the same content across regional URLs creates duplicate content issues.
- Mobile vs Desktop – Separate mobile and desktop sites can duplicate content.
Without canonical tags, all of these variations compete for the same rankings, spreading authority and relevance thinly across multiple URLs.
When to use canonical tags for eCommerce SEO
Canonical tags can be leveraged for a number of common eCommerce scenarios:
- HTTP to HTTPS – Point all HTTP pages to HTTPS version with canonical tags. HTTPS is more secure and trusted by Google.
- Non-WWW to WWW – Choose either WWW or non-WWW as primary, and canonicalize the other version.
- Category pagination – Use rel=”prev” and rel=”next” to connect paginated content sequences, and use a self-referencing canonical.
- Query parameters – Canonicalize product pages with tracking parameters to the clean URL.
- International – Use HREFLANG tags to specify alternate language versions and include a canonical tag to reference the canonical URL in each language.
- Mobile to desktop – Canonicalize mobile site pages to the desktop canonical version.
The key is identifying which URL is the strongest from an SEO perspective, and canonicalizing all other versions to that master page.
Implementing canonical tags correctly
Here are some tips for implementing canonical tags properly:
- Place the <link rel=”canonical” href=”…” /> tag in the <head> of all webpage variants you want to canonicalize.
- Point to the exact canonical page URL, including https:// and www or non-www subdomain.
- Only use a single canonical URL per page. Don’t reference multiple canonicals.
- Make sure the canonical URL actually exists and loads the same content. Don’t point to 404s.
- Use rel=”canonical” specifically for this purpose. Don’t confuse with rel=”alternate” tags.
- Use 301 redirects in addition to canonicals for optimal consolidation.
- Place canonical tags consistently on desktop and mobile versions of pages.
- Avoid canonical tags on truly unique content pages. Use for obvious duplicates only.
With this proper implementation, you can rest assured search engines will crawl and consolidate signals to your target canonical URLs.
Tracking success with Google Search Console
Google Search Console provides visibility into how Googlebot is crawling, indexing, and ranking your pages with and without canonical tags.
Here are key reports to check:
- Pages > Indexing – Verify duplicate content pages are excluded from the index in favor of your canonical versions.
- Performance report – Check click-through-rate for rankings of canonical vs duplicate URLs. The canonical should have the highest visibility.
- Sitemaps – Submit sitemaps only referencing your canonical URLs, not duplicates.
Monitoring these reports will reveal whether your canonicalization strategy is working as intended and consolidating SEO signals.
Additional tips for managing duplicate content
While canonical tags are powerful, here are some additional tips for minimizing duplicate content:
- Implement x-default hreflang tags to identify canonical URLs.
- Block or noindex duplicate content pages at robots.txt level.
- Create unique title tags and meta descriptions for each page.
- Write original content.
- Add structured data and rich snippets to differentiate similar content.
With a comprehensive duplicate content strategy using canonical tags and these optimizations, eCommerce sites can avoid dilution of SEO signals and become more discoverable in organic search.
Frequently Asked Questions
What are some examples of duplicate content issues?
Some examples include:
- The same product page on HTTP vs HTTPS
- Category pages accessed with or without the www subdomain
- Paginated category pages like /category/page1 vs /category
- Product pages with different query parameters
- Separate mobile and desktop versions of a page
When should you not use a canonical tag?
Avoid using canonical tags on pages with unique content. Only use them to consolidate duplicate or near-duplicate page versions. Don’t arbitrarily canonicalize pages that don’t have duplication issues.
How do I pick the canonical URL?
Choose the URL that is strongest from an SEO perspective – typically HTTPS, with or without www, without query parameters or fragmentation. The canonical should represent the optimal page you want search engines to index.
What if I have multiple duplicates of one page?
Use a single canonical URL tag per page. Point any duplicate versions to the one authoritative canonical page. Don’t reference multiple canonicals or you’ll dilute signals again.
How soon does canonicalization impact SEO?
It may take a few weeks or months for search engines to fully recrawl the pages and consolidate signals. But you should see improvements in site indexing, crawl frequency and rankings for the canonical over time.
Should I use 301 redirects and canonicals?
When you 301 redirect a URL, search engines can no longer access that page. Search engines will not crawl the canonical tags and, therefore, have no impact on duplicate content.
How do I track canonical tag success?
Use Google Search Console to monitor index status, click-through rate, and impressions for your canonical URLs vs duplicates. This will reveal proper implementation.
What are some other duplicate content best practices?
In addition to canonical tags: block duplicates at robots.txt level, create unique title tags and meta descriptions, use structured data and rich snippets, and avoid copying content from other sites.
Next steps
Duplicate content can significantly hurt an eCommerce site’s SEO and prevent it from reaching its full organic growth potential. Implementing a smart canonicalization strategy using the tips in this article helps consolidate optimization signals to your strongest URLs.
Prioritizing canonical tags and duplicate content management provides one of the most cost-effective ways to improve eCommerce SEO. The multitude of benefits highlighted above demonstrate why a focus on duplication can lift organic rankings and traffic.
Does your eCommerce business need help improving its duplicate content strategy? I offer expert SEO services to help eCommerce stores optimize content and lift organic visibility. Contact me to learn more about leveraging canonical tags to strengthen your eCommerce SEO.
My team can conduct an in-depth site audit to identify duplication issues and provide specific recommendations to maximize discoverability. Now is the time to get ahead of your competition in the search results.
