What is an external link?

A link from your page to another domain — the outbound citation that is sourcing to readers, an inbound link to its destination, and context to search engines.

Do external links hurt SEO?

No — the 'PageRank leak' is folk belief; Google treats linking to good sources as normal, and the citation-free thinness hoarding produces is what quality systems actually demote.

What are the rel attributes for?

Honesty markers — sponsored for paid links (required), ugc for user-generated areas, nofollow where no endorsement is meant; unmarked links are endorsements, so cite accordingly.

Growth Marketing Glossary

External Link

ex·ter·nal linknoun

The citation you give — outbound links as sourcing, trust, and the small generosity SEO myths keep advising against.

Schematic — the outbound citation

Term: External Link
Direction: Your page → another domain
Governed by: rel: nofollow, sponsored, ugc
Myth: That linking out leaks your rank

Forms & parts of speech

external link · noun

The outbound citation.

"The guide cites twelve sources with real external links - the sourcing IS the credibility."

Definition in plain terms

An external link points from your page to a different domain — the outbound half of the link economy whose inbound half this glossary's BACKLINK and EDITORIAL-LINK entries cover. To your reader it is sourcing and a service; to the destination it is the citation they call an inbound link; to search engines it is context about what your page references and trusts. The hoarding instinct — 'linking out leaks PageRank' — is one of SEO's most durable folk beliefs, and the practice it produces (unsourced claims, citation-free content) costs more credibility than any leak it imagines preventing.

The mechanics

The working rules are mostly about honesty markers. The rel attributes tell search engines what each outbound link is: nofollow (no endorsement implied), sponsored (paid placements — the disclosure Google's link-spam policies require, the EDITORIAL-LINK entry's compliance line), and ugc (user-generated areas like comments, where spam tries to live). Unmarked links are endorsements — which is precisely why generous, accurate outbound citation belongs in quality content: sourcing claims to checkable references is E-E-A-T's substance in practice (the fact-atom discipline this site's own spec enforces — every quantitative claim linked or labeled), and the evidence-shaped pages readers and raters trust link out the way good journalism does. The operational hygiene: outbound links rot (link-rot audits catch the 404s and the worse fate — domains that expired into casino redirects, your endorsement now pointing somewhere you'd never cite), affiliate links carry the sponsored marking and the disclosure copy, and target=_blank choices are UX calls, not SEO ones. The myths to retire on evidence: reasonable outbound linking does not drain rank (Google has said linking to good sources is fine and normal), and hoarding produces exactly the citation-free thinness the HELPFUL-CONTENT era demotes.

When it matters

External links matter wherever content makes claims — sourcing is the difference between assertion and evidence, and readers, raters, and the dedup-proof originality of well-cited work all reward it. They matter operationally at the rel-attribute compliance line (sponsored links marked, always) and in link-rot maintenance, where yesterday's citations quietly decay. The discipline is journalistic: cite checkable sources generously, mark the paid ones honestly, audit for rot quarterly, and let the hoarding myth die — the rank you protect by never citing anyone is the rank of a page nobody should trust.

Worked example. A finance-content site enforces a decade-old house rule - no external links, 'we don't leak authority' - and watches its YMYL rankings slide through successive core updates while cited competitors climb. The editorial reversal treats sourcing as the product: every statistical claim gains a link to its primary source (the fact-atom pattern), methodology pages cite the datasets, affiliate links get sponsored markings and visible disclosure, and a quarterly rot audit catches the citations that expired into redirect spam. Nothing else about the content changes. Two updates later the recovery is measurable - and the rater-guideline logic explains it: pages that show their work read as trustworthy because they are checkable, and the old rule had been manufacturing exactly the unsourced thinness the quality systems learned to demote. The 'leak' the rule prevented had never existed; the credibility it cost had.

Failure modes to watch. Citation-free content built on the hoarding myth; paid and affiliate links unmarked where policy demands sponsored; outbound links rotting into 404s and expired-domain spam under your endorsement; ugc areas unmarked until comment spam wears your trust; and outbound generosity confused with outbound carelessness - cite checkable sources, not whoever asked.

Synonyms & antonyms

Synonyms

external linkoutbound linkoutgoing link

Antonyms

internal linkbacklink (the inbound view)

Origin & history

Outbound linking is hypertext's founding gesture, and its marketing mythology is younger — the PageRank-hoarding belief grew from early SEO's misread of the algorithm, while the rel taxonomy (nofollow 2005, sponsored and ugc 2019) built the honesty markers Google's link policies now enforce.

Etymology: source.

Usage trends

Search interest for this term over the last five years:

View interest-over-time on Google Trends →

Common questions

What is an external link?: A link from your page to another domain — the outbound citation that is sourcing to readers, an inbound link to its destination, and context to search engines.
Do external links hurt SEO?: No — the 'PageRank leak' is folk belief; Google treats linking to good sources as normal, and the citation-free thinness hoarding produces is what quality systems actually demote.
What are the rel attributes for?: Honesty markers — sponsored for paid links (required), ugc for user-generated areas, nofollow where no endorsement is meant; unmarked links are endorsements, so cite accordingly.

Related tools & calculators

toolSEO audit tool
toolKeyword-prominence checker

Resources & people to follow

referenceGoogle — qualifying outbound links
referenceLink-rot research and citation-practice literature
referenceRGM analysis — pages that show their work are checkable; the rank protected by citing no one belongs to a page nobody should trust

Curated, non-competitor resources verified per term.

Related training

modulePerformance marketing

Disciplines

Areas of marketing where external link is a core concern:

Performance marketingGrowth strategy

Sources

trendsGoogle Trends — "external links seo"