Types of Backlinks

The Four Link Attributes

When a website links to you, the HTML can include a rel attribute that tells search engines how to treat that link. Understanding these attributes is foundational to every link building strategy.

Dofollow Links

A dofollow link is any link without a restrictive rel attribute. It is the default state of a hyperlink:

<a href="https://example.com">Great Resource</a>

Dofollow links pass full link equity from the linking page to your page. They are the primary currency of SEO link building. According to a study of 14.1 million keywords, dofollow backlinks from unique referring domains are the single strongest correlation with higher Google rankings (Backlinko, 2024).

Nofollow Links

<a href="https://example.com" rel="nofollow">Resource</a>

The nofollow attribute was introduced by Google in 2005 to combat comment spam. It tells search engines not to pass ranking credit through the link. However, in 2019 Google changed nofollow from a directive (must obey) to a hint (may choose to pass some value). This means nofollow links may still carry indirect SEO benefits (Google Search Central, 2019).

Sponsored Links

<a href="https://example.com" rel="sponsored">Partner Link</a>

Introduced in September 2019, the sponsored attribute identifies links that were paid for or part of an advertising agreement. Google expects all paid links to use eitherrel="sponsored" or rel="nofollow". Failure to mark paid links can trigger a manual penalty under Google's link spam policies (Google Search Central, 2024).

UGC Links

<a href="https://example.com" rel="ugc">User Comment Link</a>

UGC (User Generated Content) links mark links within comments, forum posts, and other user-submitted content. They carry the least direct SEO value but can still drive referral traffic and brand visibility.

Types by How They Are Earned

Beyond the technical attributes, backlinks also differ by how they are acquired. This matters because Google's link spam detection system, SpamBrain, evaluates whether links appear natural or manipulated (Google, 2024).

Editorial Links

The gold standard. A journalist, blogger, or content creator links to your page because it genuinely helps their readers. You did not ask for it, pay for it, or trade for it. Editorial links from authoritative sites account for the highest correlation with top-3 rankings (Semrush, 2025). Examples include:

• A news article citing your original research
• A blog post recommending your tool or service
• A Wikipedia reference to your data or publication

Guest Post Links

You write an article for another website and include a link back to your site. Guest posting remains effective when done for quality publications in your niche. However, 73% of link builders report that guest posting has become harder as publishers increase editorial standards (Authority Hacker, 2024). The key is providing genuine value, not just chasing a link.

Resource Page Links

Many websites maintain resource pages listing helpful tools and articles in their niche. Getting included on these pages provides highly relevant, contextual backlinks. Resource page link building has an average success rate of 5-15% per outreach email (Ahrefs, 2024).

Directory Links

Niche-specific directories (not general web directories) still carry value. Being listed in industry directories like Clutch, G2, or niche-specific associations provides both referral traffic and link equity. General web directories with no editorial review are typically worthless or harmful.

Social Profile Links

Links from your social media profiles (LinkedIn, Twitter, YouTube) are almost always nofollow. They do not directly boost rankings, but they help Google verify your brand entity and can drive referral traffic.

The Link Value Hierarchy

Not all link types are equal. Here is a practical ranking from most to least valuable:

1. Editorial links from high-authority, relevant sites (DR 60+, same niche)
2. Guest post links on quality publications (real editorial review, real audience)
3. Resource page links (curated, topically relevant)
4. Niche directory links (industry-specific, editorially reviewed)
5. Social profile links (brand signals, minimal direct SEO value)
6. Forum and comment links (UGC, almost no direct SEO value)
7. Paid links without disclosure (risk of penalty, negative value)

A healthy backlink profile includes a mix of these types. Websites that rely 100% on one link type look unnatural to Google. The average top-ranking page has backlinks from a diverse mix of 50+ unique referring domains (Ahrefs, 2025).

What to Avoid

Some link types can actively damage your rankings. Google's SpamBrain AI system detected and neutralized over 200 times more link spam in 2023 compared to when it launched (Google Spam Report, 2024). Avoid these:

• PBN (Private Blog Network) links - Networks of sites built solely for link manipulation
• Link exchanges - "I link to you, you link to me" schemes at scale
• Paid links without disclosure - Buying dofollow links without sponsored tags
• Automated link building - Software that creates thousands of low-quality links
• Irrelevant directory spam - Submitting to hundreds of general directories