Links do more than move people between pages. The HTML rel attribute describes the relationship between your page and another resource. The value noopener means: prevents a newly opened page from accessing the opener window.
What noopener means
Prevents a newly opened page from accessing the opener window.
Write it as rel="noopener" on an appropriate <a> or <link> element. Not every relationship is defined for both: the correct element depends on the link type.
Example markup
<!-- Relationship: noopener -->
<a href="https://example.test" target="_blank" rel="noopener">Open resource</a>What the browser does
This example uses <a>, which displays a regular link. The visible link text tells readers where it leads; the rel value adds information for browsers, search engines or other software.
Modern browsers generally imply noopener for target=_blank, but explicit intent can improve clarity.
Use this especially when creating browsing contexts with target="_blank" or other targets.
This relationship value does not automatically restyle the link, change its accessible name or make a new page secure. Navigation and user-facing labels still need deliberate HTML.
When to choose this token
Use noopener only when the relationship is genuinely true for that destination. If it describes a web resource, make sure that resource exists and serves the right content. For an external URL, do not confuse a relationship hint with permission, security or a redirect.
Small practice task
Create a simple test page with the example. Inspect the resulting element in Developer Tools. Change the target to another sensible file or URL, then explain whether the visible page, a network request, or only the relationship metadata changed.
Common Beginner Mistakes
- Modern browsers generally imply noopener for target=_blank, but explicit intent can improve clarity.
- Assuming
rel="noopener"has the same effect on every kind of HTML link. - Adding a relationship token when the destination does not have that relationship.
Key Takeaways
noopenermeans prevents a newly opened page from accessing the opener window.- Modern browsers generally imply noopener for target=_blank, but explicit intent can improve clarity.
- Choose a valid link element and test what the browser actually does.