How to find your competitors' backlinks (backlink gap analysis)

A backlink gap is the list of websites that link to your competitors but not to you. You find it by collecting each competitor's referring domains, collecting the sites that already link to you, and removing the ones that appear on both lists. What is left is a list of sites that have linked to a page like yours for someone else. That makes it one of the most useful link-building lists you can build, and you do not need a paid tool to start.

What is a backlink gap?

A backlink gap is the difference between the sites linking to your competitors and the sites linking to you. If three competitors each have a link from the same industry publication and your site does not, that publication is a gap link. It already links to pages on your topic, so it has shown it will link out to this kind of content.

The gap is usually measured in referring domains, not in total backlinks. A referring domain is one website. Total links counts every individual link, so one sitewide footer link can add thousands of links but only one domain. Comparing domains keeps the list honest and makes it a practical outreach list rather than a number to admire.

A backlink gap is not the same as a keyword gap. A keyword gap tells you which searches competitors target and you do not. A backlink gap tells you which sites already link to their pages on those searches. The two work well together: find the missing topic, then find who linked to the competitor's page about it.

How do I find competitor backlinks for free?

Collect each competitor's referring domains, collect your own, and keep the domains that link to competitors but not to you. You can do the whole thing with free tools and a spreadsheet. Here is the order that keeps the work small.

1. Pick two or three real search competitors

   Choose sites that appear beside you when you search for what you sell, not the biggest brands in your industry. A competitor is only useful for a backlink gap if it targets the same customers and the same topics. Two or three is enough to start; more just makes the spreadsheet slower to clean.

2. Run each competitor through the free backlink checker

   Enter each competitor's domain in MrKeyword's free backlink checker. Without an account it shows how many websites link to the domain and its 20 strongest referring domains, each with an example linking page. A free account lists more referring domains, with anchor text and the link attributes the crawler saw. Write every domain into one column of the spreadsheet, with the competitor's name beside it.

3. List the sites that already link to you

   Open the Links report in Google Search Console and export the top linking sites. Our guide to Search Console backlinks shows where each table is and how to export it. Then do the same in Bing Webmaster Tools, which has its own Backlinks tool and often finds links Google's sample leaves out. Put every domain that links to you in a second sheet or column.

4. Keep the domains that link to two or more competitors but not to you

   Match the lists by domain, not by URL. Delete any domain that already links to you. Then sort what is left by how many competitors it links to. A site that links to two or three of your competitors is a much stronger lead than one that links to a single competitor by chance. That shortlist is your backlink gap.

Repeat the export once a month and add only the new domains. The list changes slowly, and a monthly update is enough to catch new link opportunities without turning the task into a full-time job.

The backlink gap in MrKeyword

MrKeyword's Backlink gap lists the domains that link to your competitors but not to your target site, using its own crawler and its web graph. You add the competitors, and it does the set difference for you instead of leaving it to a spreadsheet.

• Where to find it. Open Find Competitors, add your target and up to four competitors, then open the Backlink gap tab. It is available on any signed-in account, including the Free plan.
• What it returns. Each row is a referring domain, with how many competitors it links to, which competitors those are, the link count MrKeyword's crawler saw, when it was last seen, and whether the domain came from MrKeyword's crawler, its web graph, or both.
• How the gap is decided. A domain that already links to your target in either source is removed from the list. That is the same rule as the spreadsheet, done in one step.
• What it does not do. Neither source covers the whole web. The web graph is domain-level, so it knows which domains link to which but not the page or anchor text, and MrKeyword's crawler has fetched far fewer pages than a large paid index. Treat the list as a strong starting shortlist, not a complete count.

Because the output is a list of domains rather than pages, the next step is still manual: open a few of the gap domains and check what they linked to. That is where the judgement below matters.

Which gap links are worth chasing?

Chase relevant, real sites that link to several competitors and publish followed links on pages a person would actually read. Not every domain in the gap is worth an email. Work through these four checks before you add a site to your outreach list.

Relevance comes first. A link from an unrelated directory passes the mechanical check but sends no one who cares. Ask whether the linking page is about something your customer is reading. If the answer is no, skip it. Our guide to link building covers how to judge a linking site.

Links to several competitors are a stronger signal than a single link. It means the site links out on this topic more than once, so there is a real chance it will link to a good page from you too.

Real sites versus spam. Watch for pages that exist only to list links, unrelated sites stuffed with exact-match anchors, and sudden bursts of links you did not earn. Google's spam policies describe link spam by name. If a gap domain is a link farm, leave it out of the list and do not contact it.

Check the link attributes. A link can carry rel="nofollow", rel="sponsored" or rel="ugc". Google treats these as hints, per its page on qualifying outbound links. Those links can still bring visitors, but do not count on them to move rankings. The anchor text of the competitor links is also worth reading; our guide to anchor text explains what a natural mix looks like.

How do I win those links?

Give the linking site a genuine reason to link to you, then ask once, clearly. A gap link is not owed to you because a competitor has it. The site linked to the competitor because the competitor had something useful. You need the same thing, or better.

• Resource pages. Many gap domains link from a page that lists tools, guides or sources. If your page fits that list and is at least as useful as what is already there, send a short note naming the page and the section it belongs in. Do not ask for a link in exchange for anything.
• Unlinked mentions. Search the gap domains for your brand name. If a page mentions you without linking, a polite request to add the link is one of the easiest wins there is, because the site has already decided you are worth mentioning.
• Better content. If a competitor's page earned links from three sites, write the page you would want to link to: more complete, clearer, and easier to use. Then tell the sites that linked to the older page that a more current resource exists. This is slow, but it is how links are earned rather than borrowed.
• Broken links. Some gap links point at pages that have since gone. Find broken outbound links on relevant sites with a broken link checker, then offer your page as the replacement if it genuinely covers the same thing.

Never buy links. Paid links that pass ranking credit are link spam under Google's spam policies, and a link scheme can hurt the site that buys it. Sponsored or paid placements should carry rel="sponsored" and are advertising, not link building. Do not swap links at scale, do not use automated outreach, and do not promise a link in return.

Free method vs MrKeyword vs paid tools

All three can produce a backlink gap. They differ in how much of the web they see, how much cleaning you do by hand, and what you pay. Start free, and move up only when the manual work becomes the bottleneck.

The gap list is only the start. The work that changes rankings is the page you improve and the outreach you send. For the full picture of what makes a link count, read what backlinks are and how to increase domain authority.

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