An external link is a hyperlink that points to any domain other than the domain where the link exists. Also called outbound links when pointing away from your site, they serve as connections between separate websites. They matter because search engines treat them as third-party votes of confidence, using them to determine ranking power, relevance, and trustworthiness.
What is External Links?
An external link targets a URL on a different domain than its source. When another website links to your domain, that is an external link to your site, commonly referred to as a backlink or inbound link. When your site links out to another domain, that is also an external link, specifically called an outbound link.
This differs from internal links, which navigate between pages within the same domain. For example, a link from yoursite.com/blog to yoursite.com/pricing is internal. A link from yoursite.com to example.com is external.
Why External Links matters
External links influence digital marketing success in several measurable ways:
- Ranking power. Search engine ranking factor survey data has shown that getting external links is the single most important objective for attaining high rankings. [Top SEOs believe external links are the most important source of ranking power.] (Moz)
- Authority transfer. Links from trustworthy domains, such as major university websites or government pages, act as strong trust endorsements. They pass link equity, or ranking power, to your target pages.
- User experience. Outbound links provide readers with additional resources, statistics, and context that enrich your content and help verify claims.
- Relationship building. Strategic external linking can foster connections with other publishers, potentially leading to reciprocal exposure and backlinks.
- Penalty avoidance. Proper use of link attributes and adherence to guidelines prevents manual actions from search engines for participating in link schemes.
How External Links works
Search engines evaluate external links using multiple metrics. Major engines assess the trustworthiness of the linking domain, the popularity of the linking page, the relevance of content between source and target, and the anchor text used in the link.
Anchor text provides crucial relevancy clues. Because humans usually write this clickable text, it reflects the target page's content. Descriptive anchor text helps search engines establish topic relevance and create knowledge hubs on the internet. However, repeating identical keyword text can trigger spam detectors, so variety is essential.
Link equity passes through external links differently depending on attributes. Standard links pass equity by default. The nofollow attribute tells Google not to pass ranking signals, though Google treats this as a hint rather than a strict directive. [Google treats the nofollow attribute as a hint, not a directive.] (Google Developers)
Types of External Links
External links fall into categories based on direction and link attributes:
| Type | Description | SEO Impact |
|---|---|---|
| Inbound (Backlink) | Links from external domains pointing to your site | Primary driver of domain authority and ranking power |
| Outbound | Links from your site to external domains | Provides user value; does not dilute your authority |
| Follow | Standard links without restrictive attributes | Passes ranking signals (equity) to target pages |
| Nofollow | Links with rel="nofollow" attribute | Treated as hint; typically does not pass equity; used for untrusted or sponsored content |
Best practices
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Use descriptive anchor text. Avoid generic phrases like "click here" or "read more." Instead, choose text that reflects the target page's topic and keywords. This improves user experience and provides context for search engines.
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Link to authoritative, relevant sources. Verify that target sites are credible and professional. Linking to low-quality or clickbait content damages your reputation and SEO. If you must link to a site you do not trust, use the nofollow attribute.
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Avoid link schemes. Do not buy or sell links for ranking purposes, participate in excessive link exchanges, or use automated programs to create links. These violate spam policies and can result in manual penalties.
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Attribute sponsored content properly. Links within sponsored or affiliate articles should include rel="sponsored" or rel="nofollow" to indicate they are not meant to influence rankings.
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Audit regularly. Check external links every one to two months. Identify broken links (404 errors) and redirects that may lead to irrelevant or malicious content if domains have expired and been repurposed.
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Vary anchor text. Do not use the exact same keyword-rich text for every link to the same target. Mix branded, partial match, and descriptive phrases to maintain a natural link profile.
Common mistakes
Mistake: Using generic anchor text like "here" or "this article." This wastes SEO value and confuses users about the destination. Fix: Replace with specific descriptions of the linked content.
Mistake: Participating in link schemes such as buying links or using automated programs to create links. Fix: Remove paid links and apply appropriate attributes to sponsored content. Focus on earning editorial links through quality content.
Mistake: Ignoring broken external links. Fix: Run monthly audits using Site Audit tools to find and remove or replace dead links.
Mistake: Nofollowing all outbound links out of fear of losing "link juice." Fix: Only use nofollow for untrusted sources, sponsors, or competitors. Normal external linking to authoritative sources does not harm your rankings.
Mistake: Linking to pages that require registration or payment without warning. Fix: Avoid such links unless the site is the official subject of your article. If included, note the access restriction.
Examples
Example scenario (Product review): A technology blog reviews wireless headphones and links to a university acoustics lab study using anchor text "frequency response research." They apply nofollow because the lab site is unfamiliar, providing reader value without fully endorsing an unverified source.
Example scenario (Legal guide): A law firm publishes a guide to data privacy and links to the official GDPR regulation with anchor text "Article 17 requirements." This follow link enhances credibility by connecting to an authoritative government domain.
Example scenario (Industry analysis): A marketing site references a competitor's industry report. They use nofollow and anchor text "Company Y's 2024 trend analysis" to provide context without passing ranking advantage to a rival.
External Links vs Internal Links
| Factor | External Links | Internal Links |
|---|---|---|
| Target | Different domain | Same domain |
| Primary SEO value | Third-party votes, authority | Site structure, equity distribution |
| Control | Limited (you control outbound, not inbound) | Complete (full site architecture control) |
| Optimization | Anchor text often not controlled | Fully optimizable for target keywords |
| Primary risk | Link schemes, broken outbound links | Orphan pages, poor navigation |
FAQ
What is the difference between a backlink and an external link? A backlink is a specific type of external link that points to your domain from another site. All backlinks are external links, but external links also include outbound links from your site to others.
How does Google treat nofollow links? Google treats the nofollow attribute as a hint rather than a directive. While it typically signals that ranking signals should not pass, Google may still use the link for crawling or indexing purposes.
Can linking to other sites hurt my SEO? Yes. Linking to low-quality, malicious, or irrelevant sites can damage your reputation. Participating in link schemes such as buying links or excessive exchanges can trigger manual penalties or algorithmic demotions.
Should I use nofollow on all external links? No. Only use nofollow for untrusted content, sponsored posts, or when linking to direct competitors you do not wish to endorse. Standard external linking to authoritative resources is expected and beneficial.
How often should I audit external links? Audit external links every one to two months. Check for broken links, redirects to unrelated content, and changes in target site ownership or quality.
What makes a good external link? A good external link points to a trustworthy, relevant domain, uses descriptive anchor text, and provides genuine value to readers by supporting claims with evidence or offering additional resources.
Is it illegal to link to a website without permission? Generally, no. You do not need permission to link to another website. However, avoid linking to material that violates copyright or sites serving malware.
