


What is the rel in html attributes and what are its common values like nofollow or noopener?
Jun 29, 2025 am 02:03 AMrel stands for "relationship" in HTML, which describes the relationship between the current document and the linked resource. Common rel values ??are: 1.nofollow, which tells search engines not to track links or pass weights, which are suitable for user-generated content or paid links; 2.noopener, which improves security and prevents new pages from accessing the window.opener attribute, which should be used every time target="_blank" is used; 3.noreferrer, which prevents the sending of HTTP Referer headers, protects user privacy; 4.canonical, which is used in
, which helps search engines identify the main version URL and avoids duplicate content problems. Choosing the right rel value helps SEO, security, and user experience, and can be used in combination, such as nofollow noopener. Correct use of rel attributes is an important part of writing specifications and secure HTML. When you see rel
in HTML attributes, it's short for "relationship" — basically telling the browser or search engines how the current document relates to the linked one. It's most commonly used with <a></a>
tags (links), and some of its values ??have important implications for SEO, security, and user experience.

Here's a breakdown of what rel
does and when to use common values ??like nofollow
, noopener
, and others.

What Does rel
Do in HTML?
The rel
attribute stands for "relationship" and describes the relationship between the current document and the linked resource. You'll usually see it on anchor ( <a></a>
) tags or link elements in the head of a page.
For example:

<a href="https://example.com" rel="nofollow">Visit Example</a>
In this case, rel="nofollow"
tells search engines not to follow that link or pass any ranking value through it.
It doesn't change how users interact with the link visually, but it affects behind-the-scenes behavior — especially from search engines and browsers.
Common rel
Values ??and When to Use Them
There are several standard rel
values. Here are the most useful ones you should know:
1. nofollow
- Tells search engines not to pass authority or trust through the link.
- Often used for user-generated content (like comments) or paid links.
- Helps prevent spam from affecting your site's SEO.
Use it when:
- Linking to untrusted or unknown sites
- Displaying paid or sponsored links
- Showing external comments or forum posts
2. noopener
- Prevents the new page from accessing the
window.opener
property. - Improves security when using
target="_blank"
to open links in a new tab.
Use it every time you open an external link in a new tab:
<a href="https://example.com" target="_blank" rel="noopener">Open in new tab</a>
Without noopener
, the new page could potentially control or slow down your original page.
3. noreferrer
- Prevents the browser from sending the HTTP
Referer
header when following the link. - Hides referral info from the destination site.
Note: Using noopener
often includes noreferrer
behavior by default, depending on the browser.
Use it if you want to protect user privacy or avoid showing where someone came from.
4. canonical
- Used in the
<head>
section to tell search engines which version of a URL is the main one. - Helps avoid duplicate content issues.
Use it on pages that have similar or identical content across different URLs (like product pages with sorting options).
How to Choose the Right rel
Value
Choosing depends on your goal:
- If you're linking out and don't want to endorse the site, use
nofollow
. - If you're opening a new tab, always include
noopener
. - If you need to manage SEO signals across similar pages, use
canonical
in the<head>
.
Also, sometimes multiple values ??can be combined:
<a href="https://example.com" target="_blank" rel="nofollow noopener">External Link</a>
This way, you block search engine crawling and keep your site secure at the same time.
Final Thoughts
Using the right rel
attributes isn't hard, but it makes a real difference in SEO performance and web security. Whether you're trying to prevent spam, protect your site from vulnerabilities, or help search engines understand your structure better, these small additions go a long way.
And honestly, once you get into the habit, it's just part of writing clean, responsible HTML.
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