What Is an External Hyperlink?
An external hyperlink is a clickable link on one website that points to a page on a different domain. It's coded with an HTML anchor tag whose href holds the other site's full URL, so clicking it takes the visitor off the current site. Moz's explainer on external links uses the same basic definition.
Here's a quick example. This link, placed on yourdomain.com, is external because example.com is a different domain:
<a href="https://example.com/guide">helpful guide</a>
Every link has three parts: the anchor tag (<a>), the href destination, and the visible anchor text. The U.S. Web Design System's link guidance stresses that link text should make the destination clear.
You'll also hear these called external links or outbound links. The label depends on whose perspective you take. A link to a subdomain such as blog.example.com is usually treated as external by SEO tools, even when the brand is the same. If terms like anchor text and crawling are new, our core SEO terminology glossary covers them, and we explain why external links matter for SEO in a dedicated guide.
External vs. Internal, Inbound and Outbound Links Explained
Link labels overlap, which causes most of the confusion. "External" describes the domain boundary. "Inbound" and "outbound" describe direction. Every backlink is another site's outbound link, and both are external links.
The table below compares the four types.
| Link type | Where it points | Whose perspective | Example |
|---|---|---|---|
| External | To a different domain | Any | yoursite.com to example.com |
| Internal | To the same domain | Your own site | /services to /contact |
| Inbound (backlink) | To your site from another | The receiver | example.com to yoursite.com |
| Outbound | From your site to another | The sender | yoursite.com to example.com |
An internal link helps visitors move around and spreads authority within your site. An outbound link is an external link seen from the sender's side. An inbound link is the same link seen from the receiver's side. For a deeper look at these terms, SE Ranking's external links overview is a handy reference.
How search engines read external links
Google uses links to discover pages and understand context, and link-based signals are one part of a larger system. We break that down in how Google's algorithm evaluates links. Google hasn't said that adding outbound links directly boosts rankings, so claims that they do are unproven.
What's better supported is the reader benefit. Citing credible sources builds trust, makes content more helpful and fits with E-E-A-T. Mediavine's piece on external links makes a similar point about choosing destinations carefully. If you want to grow authority through earned backlinks, see our notes on building authority against competitors.
rel attributes and security
The rel attribute tells search engines how you relate to the destination:
rel="nofollow": a link you don't endorse.rel="sponsored": paid placements and affiliate links.rel="ugc": user-generated content such as comments and forum posts.
Google treats these as hints, not strict commands.
Security matters too. target="_blank" opens a new tab. Modern browsers imply noopener for it, but adding rel="noopener" is still a safe habit. Adding noreferrer also hides referrer data. A full example:
<a href="https://example.com" target="_blank" rel="noopener noreferrer">source</a>
Anchor text
Make anchor text describe the destination. Avoid "click here," and use natural phrasing rather than stuffed keywords. Keyword research basics help you pick language your readers actually use. The Moz guide and the digital.gov link guidance both favour clear, specific link text.
Keeping links healthy over time
Pages move and disappear, so broken or outdated external links hurt the reader's experience. Audit them periodically, especially as search changes affect traffic. Crawlers and SEO automation tools for link audits can flag broken outbound links and track your external link profile.
In our own client audits, we commonly find outdated outbound links and missing rel attributes on affiliate links. Both are cheap to fix.
Best-practices checklist
- Link only to relevant, trustworthy pages.
- Use descriptive anchor text.
- Tag paid links as sponsored.
- Add noopener when opening new tabs.
- Check links quarterly.
Our SEO blog post checklist folds these into a full publishing routine.
External Hyperlink FAQs
Are external links bad for SEO?
No. Linking to relevant, trustworthy sources is normal and can improve reader trust. Problems arise with spammy or irrelevant destinations, or with paid links that lack rel="sponsored" or nofollow. Google hasn't confirmed outbound links directly boost rankings, so link for usefulness, not as a ranking tactic. Our Google SEO guide has more context.
How many external links should a page have?
There's no official limit or ideal number. Add an external link whenever it gives readers a source, a definition or a next step. Keep each one relevant and check that it still works. Quality and context matter far more than count. See writing SEO-friendly blog posts for practical examples.
Should external links open in a new tab?
It's a user-experience choice, not a ranking factor. If a link opens in a new tab, tell users and add rel="noopener" (noreferrer if you want to hide referrer data). Many accessibility guides advise caution with new-tab behavior.
What is the difference between an external link and a backlink?
An external link points to a different domain. A backlink is an external link seen from the receiving site: another website links to you. The same link is an outbound link for the sender and a backlink for the receiver. Moz covers the distinction too.
When should I use nofollow, sponsored or ugc?
Use sponsored for paid placements and affiliate links, ugc for links in comments or forum posts, and nofollow when you don't want to endorse a destination. Google treats all three as hints, not strict commands. SE Ranking explains each attribute in more detail.
Do external links pass link equity?
Followed links can pass signals to the destination, while nofollow, sponsored and ugc are treated as hints. Because Google doesn't publish exact weighting, focus on linking to pages you'd genuinely recommend. Mediavine offers advice on vetting destinations.
How do external links affect rankings and AI search?
Google uses links to discover and understand pages, but outbound links aren't a proven direct ranking boost. Citing credible sources supports helpful, trustworthy content, which also suits AI-driven answers. Treat it as a quality signal, not a shortcut. Our answer engine optimization article goes further.
Which on-page elements work alongside links?
Descriptive anchors, optimized images with alt text, and clear headings all support your links. Our image optimization guide shows how to handle the image side.
If you'd like a second pair of eyes on your site's link profile, Tactycs offers a free marketing strategy consultation.