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SEO
What is a canonical URL, and why does my website need it?
A canonical URL is an invisible note in the source code that establishes which address of a page is the authoritative one. This is needed because the same page is often reachable under multiple addresses — with and without "www", with attached parameters, or in language variants. Without the note, Google treats these variants as separate pages that take visibility away from each other.
A page is often reachable under multiple addresses
What's a single page to you may be several to a search engine: your homepage might respond at "www.company.at", at "company.at" without www, and additionally at addresses with tracking parameters attached, generated by newsletter links or ads, say. The content is the same everywhere, but the address differs. Google initially assesses addresses, not content — and then faces the question of which variant belongs in the results list. The canonical note answers this question unambiguously: it names the same authoritative address in every variant, comparable to a main address that all the side entrances point to.
Without the note, your pages compete against each other
If the note is missing, Google has to guess for itself which address variant counts. In the worst case, your page's assessment spreads across multiple variants: each collects part of the links and signals, and none achieves the ranking the page as a whole would have deserved. Experts call this duplicate content. The damage stays invisible, since no error message appears; the page simply shows up further back than it needs to. The canonical note costs one line in the source code, and eliminates this guessing entirely.
How we check the canonical value
The SEO audit area checks two things for every page examined. First: is a canonical note present in the source code at all? If it's missing, the report reports a serious shortcoming, since the duplicate risk affects every page on the website. Second: is the entered address complete, meaning does it start with "https://" including the domain? A partial path like "/services" counts as a formal error, since search engines expect a complete, absolute address. Both results appear in the audit report per page, so your agency can make targeted fixes.
- Open your homepage once with and once without "www", and check whether both variants work.
- Ask your agency to add a canonical note with the complete address to every page.
- Make sure the entered address starts with "https://" and includes the domain.
- Decide on one spelling as your house standard — always without "www", say — and use it consistently across all materials and ads.
FAQ
What is duplicate content?
Duplicate content means the same content is reachable under multiple addresses — with and without "www", or with parameters attached from ad links, say. Search engines initially treat every address as its own page. The assessment then spreads across the variants, and none achieves the ranking the content deserves. The canonical note solves this by naming one address as authoritative.
How do I know whether my website has canonical URLs?
The easiest way is to commission a check: our SEO audit area checks every page and reports whether the note is present and the address is complete. Anyone who wants to check themselves opens the page's source code in the browser and searches for "canonical". The line there should contain the page's complete address, including "https://".
Does the canonical URL have to be a complete address?
Yes. Search engines expect an absolute address that starts with "https://" and includes the domain — "https://www.company.at/services", for instance. A bare path like "/services" is ambiguous, and our check reports it as a formal error. The fix is simple: your agency adds the protocol and domain to the value.