What is an External Link?
On-Page SEO
An external link is a link from your website to a different domain. When you link to another site's content, that's an external link.
External links serve readers by directing them to additional resources, sources, and relevant information outside your site. They also signal to search engines that you're providing comprehensive, well-researched content.
Why external links matter
External links benefit both your readers and your SEO.
For readers
External links provide additional value. If you mention a tool, linking to it helps readers access it. If you reference data, linking to the source lets readers verify it.
Not everything you write about needs to live on your site. Sometimes the best answer is elsewhere - linking to it serves your readers.
For SEO
External links to quality sources can improve your credibility. They show you've done research and aren't just making claims without backing them up.
Google wants to rank content that's helpful and trustworthy. Linking to reputable sources supports both qualities.
For relationship building
Linking to others in your niche can build goodwill. Many people track who links to them. A thoughtful citation can be the start of a professional relationship.
When to use external links
Not every post needs external links, but many benefit from them.
Citing sources
If you reference data, statistics, research, or quotes, link to the original source. This builds credibility and allows readers to dig deeper if interested.
With source: "According to Google's research, 53% of mobile users abandon sites that take over 3 seconds to load."
This is more trustworthy than stating the stat without attribution.
Recommending tools or resources
If you mention tools, platforms, or services that readers might want to try, link to them.
When discussing keyword research, linking to Ahrefs, Semrush, or other tools you mention helps readers take action.
Providing additional context
Sometimes you mention a concept that warrants deeper explanation than you want to provide. Link to a thorough resource rather than derailing your post.
"This relies on understanding how Google's algorithm works - a complex topic we won't fully cover here."
Acknowledging inspiration
If another post inspired your approach or framework, crediting it with a link is good practice. It's transparent and respectful.
How to use external links effectively
Strategic external linking benefits everyone. Poor external linking wastes value.
Link to quality sites
Links to authoritative, relevant sites look better than links to random blogs or suspicious sites. Would you want to vouch for this site?
If you're writing about SEO, linking to Moz, Search Engine Journal, or Google's official documentation makes sense. Linking to a spam blog doesn't.
Use descriptive anchor text
Like internal links, external links benefit from good anchor text. Tell readers where they're going.
Vague: "Click here for more information." Descriptive: "Learn more about search intent on Moz's guide."
Open in new tabs (sometimes)
There's debate about whether external links should open in new tabs. Some argue it keeps readers on your site. Others say it's annoying and users can decide for themselves.
There's no wrong answer, but be consistent. Most bloggers either always open external links in new tabs or never do.
Don't overdo it
A post with fifty external links feels scattered and undermines your authority. Link where it genuinely adds value, not constantly.
Nofollow vs. dofollow external links
By default, links pass authority (they're "dofollow"). You can add a rel="nofollow" attribute to tell search engines not to pass authority through that link.
When to use nofollow
Google recommends nofollow for:
- Paid links or sponsorships
- User-generated content (blog comments, forum posts)
- Links you don't fully trust or vouch for
When not to use nofollow
For normal editorial links to quality sources, dofollow is fine. Linking to Wikipedia, government sites, major publications - these don't need nofollow.
Some bloggers nofollow all external links thinking it "preserves link juice." This is outdated thinking and unnecessary.
Common external linking mistakes
Avoid these patterns:
Linking to competitors for no reason
If you're writing about blog writing, you don't need to link to five competitor blogs. Link when it serves readers, not as a courtesy.
Broken external links
Links change and pages disappear. Periodically audit your posts for broken external links. Tools like Screaming Frog or broken link checkers can help.
Over-optimization of anchor text
If every external link has keyword-rich anchor text, it looks manipulative. Natural variation is better.
Unnatural: Every link about SEO uses anchor text "SEO optimization techniques best practices" Natural: Mix of "SEO," "this guide," "Moz's research," "according to Google," etc.
External links and SEO impact
External links aren't a major direct ranking factor for your own site. But they contribute indirectly:
- They improve content quality and comprehensiveness
- They build credibility through citations
- They improve E-E-A-T signals
- They might lead to relationship-building and backlinks
Think of external links as serving your reader first, with SEO benefits as secondary.
Balance external and internal links
A good post includes both external links (to outside sources and tools) and internal links (to your own related content).
Internal links keep readers on your site and build topical authority. External links provide additional value and credibility.
Aim for 2-5 internal links and 1-3 external links per post, adjusted based on the content's needs. Neither type should dominate overwhelmingly.
Put this knowledge into practice
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