How backlinks work
Google finds new pages mostly by following links from pages it already knows, so a backlink is often how a search engine discovers you in the first place. Once a page is known, links pointing to it also feed into ranking. Google's own spam policies open the link section by saying it uses links as an important factor in deciding how relevant a page is.
A backlink is counted per link, so one site linking to you from ten posts gives you ten backlinks but one referring domain. Links between pages on your own site are internal links, not backlinks. Most SEO tools report backlinks and referring domains side by side, and referring domains are usually the better measure of progress.
Types of backlinks
Backlinks differ by where they sit, how they were placed and what HTML attributes they carry.
- Editorial links. An editor chose to link you inside the content of a post: a list entry, a comparison table, a how-to step. These are the ones search engines want to reward. See editorial link.
- Followed and nofollow links. An ordinary link can pass ranking credit. A link marked rel="nofollow", "sponsored" or "ugc" asks search engines not to treat it as an endorsement. See dofollow link and nofollow link.
- Resource page links. Entries on a curated page of tools or guides for one audience. See resource page.
- Guest post links. A link in an article you wrote for another site, usually in the author bio. See guest post.
- Directory and profile links. Listings on directories, launch sites and profiles. A few relevant ones help people find you; hundreds of generic ones do little. See the checked list of SaaS directories.
- Paid links. Links someone paid for. Google requires these to carry rel="sponsored" or rel="nofollow"; otherwise they count as link spam.
How backlinks are earned
The reliable way is to be useful on a page that already covers your topic and then ask the person who edits it. For a product, that means existing best-of lists, "[competitor] alternatives" and comparison pages, resource pages, and how-to guides for the job your product does. How to get backlinks ranks the main methods by effort and risk, and the link outreach guide covers the pitching itself.
- Outreach to existing posts. Find posts where you'd genuinely fit and ask the editor to add you. The search string builder finds them; alternatives posts and best-of lists have their own playbooks.
- Something worth citing. Original data, a free tool or a reference page gives writers a reason to link without being asked.
- Digital PR. Pitching journalists with stories, data or expert comment. See digital PR and digital PR for SaaS.
- Mentions and lost links. Ask sites that already name you to add the link, and recover links that disappeared. See unlinked mention and link reclamation.
- Broken links. Offer your page as a replacement for a dead link on someone else's. See broken link building.
What makes a backlink high quality
No single metric decides it. These are the signals that matter most, roughly in order. What makes a backlink high quality goes through each one, and how to choose sites to pitch turns them into a scoring sheet.
- Relevance. The linking page is about your topic and its readers could use your product.
- The page gets read. It ranks for searches in your niche or has an audience, so the link can send visitors.
- Placement. The link sits in the body of the content, not a footer, sidebar or comment.
- Followed. No nofollow or sponsored attribute, checked with the nofollow link checker.
- Natural anchor text. Your brand name, the URL or a plain description. Check your mix with the anchor text checker.
- An editorial decision. The site doesn't sell links to anyone who pays. Domain Rating helps compare sites but says nothing about relevance.
Backlinks to avoid
Google's spam policies list buying or selling links that pass ranking credit, excessive link exchanges, large-scale guest posting with keyword-rich anchors, and automated link creation as link spam. Since its December 2022 link spam update, Google says its SpamBrain system detects sites that buy links and sites that exist to sell them, and neutralises those links. That usually means paid links simply stop counting, so the money is wasted. Should you buy backlinks? and what backlinks cost cover the trade-offs, and PBN and toxic backlinks explain the worst cases.
Keeping the backlinks you earn
Links you earn can vanish when a post is rewritten, a site is redesigned or an editor switches outbound links to nofollow. Check won links on a schedule and ask about any that disappear while the editor still remembers you. Backlink monitoring and recovering lost backlinks explain how. BacklinkGenie does this for every link it wins: it confirms the link on the live page, re-checks it every week and emails you if it's removed or made nofollow.
Example
A university writing guide that links to margin.example from its "note-taking tools" section gives Margin a backlink.
Putting it into practice
Where to use it: How to choose sites to pitch, Nofollow link checker and Link prospecting search strings. For the longer version, read twelve ways to get backlinks, ranked by effort and risk.
Sources
- Google Search Central: Spam policies for Google web search (link spam)
- Google Search Central: In-depth guide to how Google Search works
- Google Search Central: Qualify your outbound links to Google
- Google Search Central Blog: Evolving "nofollow", new ways to identify the nature of links (September 2019)
- Google Search Central Blog: December 2022 link spam update