What Is a Backlink? A Plain-English Guide

A backlink is a link on another website that points to a page on your website. If a baking blog publishes a sourdough recipe and links to your flour shop's rye flour page, that link is a backlink for you. For the baking blog it is an outbound link; for you it is an inbound link. It's the same link seen from two sides.

That simple idea sits under a large part of search engine optimization, and under a lot of bad advice too. This guide covers what a backlink is at the HTML level, how the different link attributes work, why search engines care about links, what Google explicitly calls link spam, and how to earn links that keep helping you for years.

What a backlink looks like in HTML#

Every standard link on the web is an anchor element:

<a href="https://example-flour.com/rye-flour/">stone-ground rye flour</a>

Three parts matter:

• The href attribute is the destination URL. That page is the one receiving the backlink.
• The anchor text is the clickable text, here "stone-ground rye flour". It tells readers and search engines what to expect on the other side. There's a full anchor text guide in this series.
• The rel attribute is optional. When it's present, it qualifies the relationship between the two sites.

Google's crawlers reliably extract links from <a> elements that have an href. Google's link best practices documentation notes that most links in other formats, such as a <span> with a JavaScript click handler, won't be parsed. So if a site "links" to you with a script-driven button instead of a real anchor, it may not count as a link for Google at all.

Dofollow, nofollow, sponsored and ugc#

"Dofollow" isn't a real attribute. It's shorthand for a normal link that has no qualifying rel value. Google documents three values you can add to qualify a link:

You can combine values, for example rel="ugc nofollow". According to Google's guide to qualifying outbound links, links with these values generally won't be followed, although the linked page can still be discovered some other way, such as through a sitemap or links from other sites. Since 2019, Google has treated these attributes as hints rather than strict commands.

The practical takeaway is simple. A nofollow link isn't worthless: it can send visitors, introduce your brand to new readers, and lead someone to link to you editorially later. But you shouldn't expect it to carry ranking signals the way an editorial link does.

If you're the one doing the linking, one rule matters above the others: when a link was paid for, mark it sponsored (or nofollow). That isn't a courtesy. It's the line between a legitimate ad and a link scheme.

Why backlinks matter#

Google's documentation describes links as something it uses both to find new pages to crawl and as a signal when determining how relevant pages are. Those are two separate jobs.

Discovery#

Crawlers move around the web by following links. A new page with no internal links pointing to it and no backlinks is hard for a search engine to find. A sitemap helps with this (see how to create a sitemap), but links remain the main way pages get discovered.

Relevance and trust#

A link from a relevant, trusted page works like an editorial reference: someone looked at your page and decided it was worth sending their readers to. The anchor text and the words around the link also help describe what the linked page is about.

Links are not the whole story, though. Content that doesn't answer the searcher's question won't hold rankings no matter how many links point at it. Think of backlinks as something that amplifies good pages, not something that rescues weak ones.

Quality beats quantity#

A handful of genuinely relevant, editorial links will usually do more for you than hundreds of links from pages nobody reads. When you look at a link, or a link opportunity, ask these questions:

1. Is the linking page relevant? A link from a baking blog to a flour shop makes sense. A link from a car-insurance directory doesn't.
2. Was it an editorial choice? A person decided to link because it helps their readers, not because a form auto-inserted it.
3. Is the site real? It has an audience, publishes original content, and isn't a network of near-identical pages built to host links.
4. Where is the link placed? A link in the body of a relevant article carries more context than one buried in a sitewide footer or a long list of unrelated links.
5. Can it be crawled? The linking page should be indexable, and the link should be a real <a href>.
6. Would anyone click it? If you can't imagine a single reader following the link, it probably isn't doing much for you.

To compare linking domains quickly, you can use our Domain Authority Checker. It shows the NewBacklink Domain Score, our own metric calculated from the Common Crawl web graph. It is not Moz DA, and like every third-party score it's an estimate. Google doesn't use any third-party domain metric, so treat these numbers as a rough filter, never as the deciding factor.

What Google considers link spam#

Google's spam policies define link spam as creating links to or from a site mainly to manipulate search rankings. The examples Google lists include:

• Buying or selling links for ranking purposes, including exchanging money, goods or services for links, or sending someone a free product in exchange for a link
• Excessive link exchanges, where sites link to each other purely to cross-link
• Using automated programs or services to create links to your site
• Requiring a link as part of a terms of service or contract without letting the other party qualify it
• Advertorials or native ads where payment is made for articles that carry ranking-passing links
• Low-quality directory or bookmark site links, and links hidden in widgets distributed across many sites
• Keyword-rich links dropped into forum comments, signatures or profiles

Google also states clearly that buying links for advertising is a normal part of the web, as long as those links are qualified with rel="sponsored" or rel="nofollow". The problem isn't paying for exposure. The problem is paying for links that pretend to be editorial.

When Google detects link spam, those links may simply be ignored, and in more serious cases a site can receive a manual action. Either way, the money and time spent on the links is wasted.

How to earn backlinks#

There's no shortcut that works reliably, but there are proven approaches that don't put your site at risk.

1. Publish something worth citing. Original data from your own business, a detailed how-to that covers the edge cases, a free tool, a template, or a clear definition page. People link to resources that save them work.
2. Be a source. Journalists and bloggers need expert input. Answering their questions with specific, usable information often leads to a citation.
3. Write guest posts for real audiences. Pick sites your customers actually read, and write something that helps them. Our how to find guest post sites guide covers vetting. The Guest Post Finder opens each suggested site live and only confirms pages that actually explain how to submit.
4. Turn mentions into links. If a site already mentions your brand without linking, a short, polite note asking for a link is often welcome, because it helps their readers find you.
5. Fix broken links for others. When a resource page in your niche links to a page that no longer exists, you can suggest your page as a replacement. Our Broken Link Checker scans a page and lists its dead links.
6. Reclaim links you already earned. If you deleted or moved pages that had backlinks, redirect them to the closest relevant page. See how to check backlinks for how to find these.
7. Use real relationships. Suppliers, partners, industry associations, local organizations and events often link to the businesses they work with.

Example: evaluating one link opportunity#

Say you sell handmade leather wallets and a menswear blog offers to publish a guest article from you. Before you write a word, run through this:

1. Open the blog and read three recent posts. Are there real authors with bios? Are posts dated recently?
2. Check topical fit. Menswear and leather goods overlap well. If the same blog also publishes crypto, casino and loan posts, that's a warning sign.
3. Look for a price list. A page advertising "dofollow guest posts" for a fee means the site sells links. Any paid link must carry rel="sponsored", and a site promising otherwise is asking you to break Google's policies.
4. Look at the domain's history. A domain registered last month claiming a decade of publishing deserves a closer look. See how to check domain age.
5. Ask whether a reader would click. If your link would sit naturally in an article about caring for leather accessories, it's a good fit. If it would feel forced, write a different article or pass.

Common myths#

• "Nofollow links are useless." They can still send traffic, and Google treats the attribute as a hint.
• "Google uses domain authority scores." It doesn't. Third-party scores are estimates.
• "You should disavow every weak link." Google says most sites never need its disavow tool.

The short version#

A backlink is a link from another site to yours. The good ones are editorial, relevant, crawlable and placed where readers will see them. Paid links are fine only when marked sponsored or nofollow. The most dependable way to get backlinks is still to publish things other people want to reference, then make sure the right people see them.