What Are Backlinks? How to Judge Link Quality
A backlink is a link from someone else’s website to yours. When a respected industry site links to your guide, it sends readers your way and tells search engines that someone outside your company found the page worth citing. Backlinks remain one of the clearest signals search engines use to judge which pages deserve to rank, but only links given on merit count. Bought or traded links can hurt you.
Key takeaways
- A backlink is a vote from another site, and relevance matters more than raw numbers.
- Links you pay for must be marked rel="sponsored", or they break Google's link spam policy.
- Links decay. A large share of links on the web disappear within a few years.
- Check your profile quarterly for lost links and unnatural patterns.
Why backlinks matter
Links do two jobs. They help search engines discover your pages, and they act as evidence of trust. In competitive markets, it’s very hard to reach page one without them. Ahrefs found a clear correlation between the number of sites linking to a page and its search traffic. Correlation isn’t proof, but it matches what most SEO practitioners see.
Backlinks also matter beyond Google. Mentions and citations on credible sites shape how AI tools describe your brand, because those tools learn from, and search, the same web.
- 96.55% of pages in Ahrefs' index got no Google traffic; lack of backlinks was a key reason it identified Ahrefs search traffic study, 2023
- 66.5% at least this share of links to sites over the last nine years are now dead Ahrefs link rot study, 2024
How to judge a backlink’s quality
Not all links are equal. Ask five questions about any link, existing or proposed.
| Question | Good sign | Warning sign |
|---|---|---|
| Is the site relevant to your field? | Same industry or audience | Unrelated topics, many languages, everything for sale |
| Was the link given editorially? | Earned by your content or expertise | Paid, swapped or required as a condition |
| Does the site have real readers? | Organic traffic, active community | No traffic, only exists to sell links |
| Is the anchor text natural? | Your brand name or a descriptive phrase | Exact-match money keywords repeated across many sites |
| Is the link in context? | Inside the body of a relevant article | Footer, sidebar, sitewide or a list of unrelated links |
A third-party score such as domain authority can help you sort lists of sites, but it’s not a Google metric. The five questions matter more.
Myth vs fact
- MythNofollow links are worthless.
- FactThey still send visitors and build brand awareness, and Google treats nofollow, sponsored and ugc as hints, not strict rules. A natural profile includes a mix.
- MythMore backlinks always means better rankings.
- FactMany low-quality or paid links can trigger Google's link spam systems. A handful of relevant, editorial links is worth more than hundreds of directory links.
Example from our work
The links worth having usually come from doing something people want to reference: original data, a useful tool, a clear point of view. I'd rather a client earn five links from sites their buyers actually read than buy a package of fifty from sites nobody visits. If you wouldn't want the link without the SEO value, it probably isn't worth the risk.
How to check and grow your backlinks
A quarterly backlink review
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Export your links
Use Google Search Console's Links report for free, and a tool such as Ahrefs or Semrush for more detail.
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Find lost links
Look for links that pointed to pages you deleted or moved. Redirect those URLs to the closest live page.
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Spot risky patterns
Look for sudden spikes, many links with the same keyword anchor, or links from unrelated foreign-language sites.
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Study competitors
See which sites link to two or more competitors but not to you. These are your most realistic targets.
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Earn new links
Publish something worth citing, such as original data, a useful tool or an expert view, then tell the people who write about your topic.
The full process of earning links is covered in link building. Tactics that cross the line are listed in black hat SEO.
Related terms
- Link building: the work of earning backlinks.
- Domain authority: a third-party score based largely on links.
- Guest posting: one way links are earned, with real risks.
- Black hat SEO: link tactics that break Google’s rules.
Frequently asked questions
How many backlinks do I need to rank?
There is no fixed number. It depends on how strong the pages already ranking for your keyword are. Look at the top five results in a backlink tool and count their referring domains. That gives a realistic target for that specific query.
What is the difference between dofollow and nofollow backlinks?
"Dofollow" is shorthand for a normal link with no rel attribute. A nofollow link has rel="nofollow", which asks search engines not to pass ranking credit. Google also supports rel="sponsored" for paid links and rel="ugc" for user-generated content, and treats all three as hints.
Can backlinks hurt my site?
Links you didn't create are usually ignored if they're spammy. Problems arise when you take part in link schemes: buying links, large-scale link exchanges or keyword-stuffed guest posts. Those can lead to lost rankings or a manual action.
How do I check my competitors' backlinks?
Enter their domain in a backlink tool such as Ahrefs, Semrush or Moz. Filter for links from relevant sites, then look for patterns, such as industry lists, data studies or podcasts, that you could also earn.
How TechDella can help
Our SEO service includes digital PR and content made to be cited, with no paid link schemes.