In the world of SEO, links are like votes. When you link to another website, you are essentially telling Google: “I trust this site, and I am willing to pass some of my own website’s authority (PageRank) over to them.”
By default, every link you create is a “dofollow” link. But what happens if you need to link to a website that you don’t completely trust? Or what if someone pays you to put a link on your blog? If you pass your hard-earned SEO authority to spammy or paid websites, Google might actually penalize your site.
This is exactly why the rel="nofollow" attribute was invented.
Over the years, Google has evolved this system to include two additional, highly specific attributes: rel="ugc" and rel="sponsored". In this guide, we will break down exactly what these tags mean, when to use them, and how to avoid massive SEO penalties.
What is a Nofollow Link?
Introduced in 2005 to combat blog comment spam, the rel="nofollow" attribute is a simple piece of HTML code added to a hyperlink.
<a href="https://example.com" rel="nofollow">Click Here</a>
When Googlebot crawls your page and sees this tag, the instruction is clear: Do not pass my PageRank to this target URL, and do not use this link to help the target rank higher. Note: In 2019, Google updated its algorithm to treat nofollow attributes as “hints” rather than strict directives. While they generally won’t pass authority, Google reserves the right to evaluate the link on its own terms.
The 2019 Evolution: UGC and Sponsored Attributes
As the internet grew, Google realized that grouping every single untrusted link under “nofollow” wasn’t giving their algorithm enough context. Is it a spam comment? Is it a paid advertisement? To clarify this, Google introduced two new attributes.
Here is the breakdown of the three attributes and exactly when you should use them:
1. rel=”sponsored” (For Paid and Affiliate Links)
If money, products, or services changed hands in exchange for a link, you must use the rel="sponsored" attribute.
- When to use it: Affiliate links (Amazon, ClickBank), sponsored blog posts, banner ads, and paid guest posts.
- Why it matters: Google’s Webmaster Guidelines strictly prohibit buying or selling links to manipulate rankings. If you use standard dofollow links for your affiliate products, you are risking a manual penalty that can wipe your site off the search results.
- Example:
<a href="https://affiliate.com/product" rel="sponsored">Buy Now</a>
2. rel=”ugc” (User Generated Content)
UGC stands for User Generated Content. This attribute is designed for links that are created by your website’s visitors, not by you or your editorial team.
- When to use it: Blog comment sections, forum posts, profile pages, and public Q&A boards.
- Why it matters: You cannot control what your users post. By automatically applying
rel="ugc"to user submissions, you protect your site’s authority from being drained by spammers dropping links to shady websites. - Example:
<a href="https://spammysite.com" rel="ugc">Check out my site</a>
3. rel=”nofollow” (The Catch-All)
The traditional nofollow tag is now used as a general catch-all for cases where you want to link to a site but do not want to endorse it or pass ranking credit.
- When to use it: Linking to a competitor you don’t want to help, referencing a low-quality site as an example, or when you are just unsure about the target site’s credibility.
Can You Combine Attributes?
Yes! Google supports combining multiple attributes separated by a space. For example, if you have a sponsored link inside a user-generated forum post, you can write:
<a href="https://example.com" rel="ugc sponsored">Paid Link</a>
It is also completely acceptable to combine the traditional nofollow with the new tags for backward compatibility with older search engines: rel="nofollow sponsored".
How to Audit Your Website’s Link Attributes
If you are a blogger doing affiliate marketing, accidentally leaving your Amazon links as “dofollow” is a ticking time bomb for your SEO. You need to ensure your outbound links are tagged correctly.
Instead of manually digging through your HTML source code, you can use FunSEO to audit your links instantly.
Our free SEO scanner acts as an automated QA tool for your content. When you run a scan (no login required), FunSEO will:
- Extract all links on your webpage.
- Calculate your Dofollow vs. Nofollow ratio: Ensure you maintain a natural, healthy outbound link profile.
- Verify your link health: FunSEO checks a sample of your links to ensure they aren’t pointing to dead (404) pages.
Stop guessing whether your affiliate links are putting your site at risk. Run a fast, free scan on FunSEO today and take total control of your website’s link equity.