Types of Backlinks - DoFollow, NoFollow and Toxic Links
Backlinks are a central part of off-page SEO. They signal to search engines that your content is credible, referenced, and relevant. But not all backlinks carry the same weight - and not all of them help you rank better.
Understanding the different types of backlinks is critical when planning or auditing your link building efforts. The type, source, and context of a link all contribute to how search engines interpret it. Some links improve visibility and domain authority. Others are neutral, and a few can be harmful if left unmanaged.
This article breaks down the major types of backlinks - focusing on how they function, how search engines treat them, and when they’re beneficial or risky.
What Is a DoFollow Link?
A “DoFollow” link is the default type of backlink. It passes ranking signals (also known as “link equity” or “PageRank”) from the referring site to the linked page. In Google’s eyes, it’s a vote of confidence.
DoFollow links are especially valuable when they come from:
- High-authority websites
- Topically relevant content
- Editorially placed contexts (not user-submitted or spammed)
You don’t need to add any special code to make a link DoFollow - this is the standard behavior unless otherwise modified. For example:
<a href="https://example.com">Visit Example</a>Search engines follow this link and associate value with the destination URL.
Why DoFollow Links Matter for SEO
These links are what most SEO professionals aim for when running content promotion or outreach. DoFollow backlinks help:
- Improve keyword rankings
- Pass domain or page-level authority
- Boost crawling frequency
- Increase brand credibility
They’re especially important when trying to outrank competitors for high-value commercial queries.
What Is a NoFollow Link?
A NoFollow link includes a rel="nofollow" attribute, which tells search engines not to pass authority from the linking page to the target page.
Example:
<a href="https://example.com" rel="nofollow">Visit Example</a>These links were originally introduced by Google to combat comment spam and other manipulative linking practices. While search engines may still discover and crawl these URLs, they typically don’t use them to influence ranking.
Where NoFollow Links Commonly Appear
- Blog comments
- Forum posts
- Wikipedia entries
- Press release syndication
- Paid advertisements
- UGC platforms (when tagged)
- Some large media sites (by policy)
Even though they don't pass PageRank, NoFollow links still have value. They can:
- Drive referral traffic
- Improve content discoverability
- Balance a link profile with natural diversity
- Support brand exposure
Google has stated it may treat NoFollow links as “hints” rather than strict directives, especially if the link is contextually relevant.
Other Link Attributes: Sponsored and UGC
In addition to NoFollow, Google recognizes two other attributes introduced to help categorize backlinks more precisely:
rel="sponsored"- used for links that are part of paid relationships, such as affiliate placements or advertorialsrel="ugc"- short for “user-generated content,” used for links in comment sections, forums, and user submissions
These don’t pass traditional ranking value but help maintain transparency and prevent penalties from link manipulation.
In some cases, multiple attributes are used together:
<a href="https://example.com" rel="nofollow sponsored">Sponsored Link</a>This hybrid approach helps clarify the link’s context for search engines.
What Are Toxic Links?
Toxic links are backlinks that may harm your site’s visibility or reputation in Google’s algorithm. These often come from:
- Spammy or irrelevant websites
- Link farms or private blog networks (PBNs)
- Hacked sites or expired domains used for manipulation
- Irrelevant foreign domains with no contextual fit
- Sites penalized or deindexed by search engines
Google’s algorithms are designed to ignore many of these links. However, if your site has a high concentration of toxic or unnatural links (especially those built intentionally) it could trigger manual action or algorithmic filtering.
How to Identify and Handle Toxic Links
Use tools like Ahrefs, Semrush, or the Google Search Console’s “Links” report to monitor your backlink profile. Flags for toxicity include:
- Extremely low domain authority
- Repeated exact match anchor text
- Large volume of links from unrelated industries or languages
- Sites with no organic traffic or questionable outbound linking behavior
If you find a pattern of toxic backlinks:
- Try to remove them - by contacting the site owner (often not effective)
- Use the disavow tool - to signal Google not to count them against your site
- Audit regularly - to keep your backlink profile clean and diverse
(See Link Audits & Disavow Tools Explained for the complete process.)
Putting It All Together
A healthy backlink profile includes a mix of:
- DoFollow links from high-authority and relevant sources
- NoFollow and sponsored links used where appropriate
- A natural anchor text distribution
- Ongoing monitoring for low-quality or toxic signals
Search engines look for patterns, not individual links. Prioritize building links that make sense contextually, serve users, and enhance your site’s reputation - rather than chasing quantity or shortcuts.