Inbound links are links from other websites to yours, also called backlinks. Outbound links are links from your website to other websites. Internal links connect pages within your own site. All three can help search engines and AI systems understand what your pages are about, but in different ways, and not every link helps.
The short answer
A backlink from a relevant, respected site is a vote of confidence. A backlink from a spammy or paid source is noise at best and a risk at worst. Outbound links show your sources. Internal links connect your own pages, and you control every one of them, so start there. In AI search, one large study found visibility tracks brand mentions more closely than link metrics, though that is a correlation, not a recipe.
When I first wrote this post in 2017, I called backlinks “single-handedly the most important ranking factor”. I would not say that now. Links are one signal among several. Being mentioned by sites people trust, and having a clearly structured site, also shape how you show up, especially in AI answers.
What is the difference between inbound and outbound links?
An inbound link is a link on another website that points to your website. An outbound link is a link on your website that points to another website. The same link is outbound for the site that places it and inbound for the site it points to. Internal links stay within one website.
| Link type | From | To | Main value |
|---|---|---|---|
| Inbound link (backlink) | Another website | Your website | Signals trust and authority; brings referral visits |
| Outbound link (external link) | Your website | Another website | Credits sources; helps readers and shows context |
| Internal link | One page on your site | Another page on your site | Helps discovery, shows structure, shares authority |
Caption: Inbound, outbound and internal links compared.
Why do inbound links matter for SEO?
Inbound links matter because Google treats links from other websites as one signal of a page’s importance and trust. Google’s local ranking guidance, for example, lists links from other websites as part of prominence. Links from relevant, respected sites count far more than many links from low-quality ones. Buying links that pass ranking credit breaks Google’s spam policies.
I learnt the cost of the wrong links on my own domain. Around 2018, a paid link-building arrangement for my site bought guest-post and author-bio links, all pointing at my homepage with the exact words “web design Sydney”. There was no manual action and no warning. My homepage simply disappeared from Australian results for about a year, while it still ranked first in other countries, and most of my traffic went with it. It came back almost exactly a year later and never returned to the top five for that phrase. Since then I earn links and never buy them. My notes on recovering from a Google penalty cover what to do if it happens to you.
Good ways to earn inbound links in 2026:
- Publish original data, research or tools that others want to reference.
- Contribute expert commentary to journalists and industry publications.
- Speak at events and appear on podcasts, which usually link to speakers.
- Be listed in genuine industry associations and directories.
- Build relationships with partners who can reference your work.
My guide to link building in the AI era covers what still works and what to avoid.
Do outbound links help or hurt your SEO?
Use outbound links where the source helps the reader verify or understand the claim. I would not add or remove citations to chase a fixed outbound-link count. Normal editorial links and paid ranking-credit links need different treatment.
I link to primary sources throughout my posts, because evidence is what makes content credible to both people and AI systems. The only outbound links to avoid are to low-quality, unrelated or spammy sites.
| Attribute | Use it for |
|---|---|
| No attribute (followed) | Normal editorial links you vouch for |
| rel=”sponsored” | Paid links, affiliate links and sponsorships |
| rel=”ugc” | Links in comments and forum posts |
| rel=”nofollow” | Links you do not want to vouch for, when the others do not fit |
Caption: Link attributes and when to use them, based on Google’s link best practices and its guide to qualifying outbound links.
Here is what each looks like in practice on one page: a cited statistic, a podcast sponsor and a reader’s comment.
<!-- Editorial: a source I cite and vouch for -->
<a href="https://www.abs.gov.au/">ABS business counts</a>
<!-- Sponsored: the episode's paid sponsor -->
<a href="https://sponsor.example/" rel="sponsored">Our sponsor</a>
<!-- UGC: a link a reader left in the comments -->
<a href="https://reader.example/" rel="ugc">Reader's site</a>How do links affect AI search visibility?
Links can feed AI search indirectly, because some AI answers draw on pages that already rank well in search. How much depends on the engine and the question. Ahrefs’ December 2025 study of 75,000 brands found visibility in ChatGPT, Google’s AI Mode and AI Overviews correlated more strongly with branded web mentions (about 0.66 to 0.71) than with link metrics such as Domain Rating (about 0.27 to 0.33).
The Ahrefs study is observational and selected 75,000 brands meeting its domain-strength and keyword criteria. Established brands may earn both mentions and visibility for other reasons. It does not establish a reward for each link or mention, or predict the outcome for a small Australian site.
In the agentic web, the goal of “link building” becomes “being worth mentioning”. Original research, clear expertise and appearances on podcasts and lists earn both links and mentions.
How should you use internal links?
Use internal links to connect related pages and make important content reachable. Write descriptive anchors that identify the destination. Google can discover standard <a href> links, including ones inserted by JavaScript; a click handler on a different element is not a reliable substitute. Other crawlers may render differently.
- Link from each post to the main guide on its topic.
- Link related posts to each other where it genuinely helps the reader.
- Keep important pages within a few clicks of the homepage.
- Fix internal links that point to redirected or deleted pages.
My guide to WordPress SEO covers the settings that support good internal linking, and my guide to WordPress tags covers using taxonomy without creating thin pages.
For each important link, check four things: the intended destination, its final response, the words in the anchor and the relationship being declared. A citation should support the nearby claim; a navigation link should help the reader continue. Do not turn every external source into a new-tab popup or an affiliate placement.
What is anchor text and why does it matter?
Anchor text is the clickable text of a link. It tells people and search engines what the linked page is about. Descriptive anchors such as “WordPress maintenance cost guide” help. Generic anchors such as “read more” do not. Over-optimised anchors that repeat the same exact keyword on every inbound link can look manipulative.
What to do next
- Check which sites link to you, using Google Search Console’s Links report.
- Find your three most valuable pages and add internal links to them from related posts.
- Replace “click here” anchors with descriptive text.
- Add outbound links to primary sources for every statistic you quote.
- Plan one piece of original research or expert commentary that others would want to cite. For the wider plan, see my guide to SEO in the AI search era.
Frequently asked questions
Are backlinks the same as inbound links?
Yes. Backlink and inbound link mean the same thing: a link from another website to yours. Some people also call them incoming links or external links pointing to you.
How many outbound links should a page have?
There is no ideal number. Link wherever it helps the reader verify a claim or learn more, typically to primary sources for statistics and to genuinely useful resources. Avoid linking just to hit a number, and avoid long lists of unrelated links.
Do nofollow links help SEO?
Don’t count on them for rankings. Google has treated nofollow, sponsored and ugc as hints since 2019, so it may or may not use a marked link, and it doesn’t publish how much credit, if any, flows. Value them for what they reliably bring: visitors, brand awareness and mentions. A nofollow link from a respected publication is still worth having.
Do internal links help rankings?
Yes. Internal links help Google discover pages, understand how they relate, and see which pages you consider most important. A clear internal link structure is one of the few ranking factors fully in your control.
Should I buy backlinks?
No. Buying links that pass ranking credit breaks Google’s spam policies and can lead to a manual action or lost rankings. Paid placements should be marked rel=”sponsored”. Invest in content and relationships that earn links and mentions instead.
