Best backlink tools compared, on what each index can actually see

Backlink data is the one part of this market that genuinely cannot be done free at depth, and the reason is structural. Google shows you your own links in Search Console. Everything you want to know about somebody else's links has to come from an independent crawl of the web, and building one of those is the entire business of a handful of companies.

So the criterion here is not features. It is what does the index contain, and how much of it does your tier release to you? Both numbers are published, which makes this the most checkable comparison in the whole tool market.

What each vendor publishes about its index and your ceiling

The metric question, answered honestly

Domain Authority, Trust Flow, Domain Rating and their equivalents are each vendor's own model of how strong a site is. None of them is used by any search engine. That does not make them useless: they are comparative, so ranking two sites on the same scale is legitimate and useful. It makes one specific use of them wrong, which is treating a number as a target to reach, because you would be optimising for a third party's model rather than for anything a search engine does.

The data to act on is not the score. It is the list of pages linking to the page that outranks yours, read individually, because the only question that produces a plan is why would somebody link to mine instead.

The one month method, which is cheaper than any annual plan

Pick your three real competitors. Buy one month of one index. Export the referring domains for the specific pages beating you, not for their whole site. Read the pages that link out, sort them into the ones you could honestly earn and the ones you could not, and write the plan. Then cancel and work the plan for three months. Almost nobody needs continuous access to a link index, and the ones who do are agencies and publishers with a weekly prospecting process.

The thing to avoid buying is a link, rather than a tool. That is a different market with a different risk profile, and no amount of index data makes it safer.

The one check none of these tools runs, and who sells it

Every tool on this page measures a search engine. None of them measures the other place your buyer now asks, which is an assistant: ChatGPT, Gemini, Perplexity, Claude and Google AI Overviews compose an answer for each asker, naming some businesses and not others, and there is no index a crawler can read to find out whose name came up. A citation inside an assistant answer is not a link and will never appear in a backlink index, which is why a growing share of the mentions that influence buyers is invisible to every tool in the table above.

AI Knows Us sells that one measurement and nothing else. We are not an SEO tool and we are not in the ranking above, because a buyer who came here for a crawler or a keyword index should buy one of the tools named above instead. What we do is ask your buyer question in all five apps on a schedule and record which businesses were named. Our own figures, from the rendered text of our llms.txt read on 21 October 2026: one credit is one buyer question on one app once, most checks cost one credit and a Claude check costs three because Claude costs more to run. The published US floor is $149 a month for SEO Start, and that same file says SEO Start watches 0 buyer questions on 0 engines, so it is a demand harvest rather than an engine watch. The first tier that watches the five engines is Growth at $299 with 100 buyer questions and 1,200 scheduled answers a month. A managed option is published in rupees only, Rs 88,499 to Rs 2,35,999 a month at a three month minimum, so we are not going to convert it for you.

Where the tools on this page beat us, plainly. Ahrefs Brand Radar, read on 21 October 2026, tracks prompts on ChatGPT, AI Overviews, AI Mode, Gemini, Perplexity, Copilot and Claude. AI Mode and Copilot are two surfaces we do not read at all, and its page publishes an overage price of $0.020 per check and the cost of a Claude update at 8 checks, which is a level of unit disclosure worth holding every vendor to, us included. Semrush, whose SEO and AI search pricing page we read the same day, sells AI visibility inside the suite you may already be paying for, with 50 prompts tracked daily and 300 AI visibility reports a day on its Starter tier. Moz now publishes AI Explorer, described on moz.com as showing what the top AI agents say about your brand. If you already pay one of those three, their module is the cheaper route and you should take it. We are the single purpose option for somebody who does not want a suite.

Before you pay for an index

No competitor price table is reproduced on this page. What is quoted instead is the published limit that sets a tier, because a limit is the vendor's own statement of what you get and it does not move with the country you are reading from. That matters more than it sounds: on 21 October 2026 a fetch of one vendor's US pricing page from this machine returned Indian rupee prices, because the request left from an Indian address. A 200 response can still be the wrong page.

Read your own link report in Search Console first, free, because it is the only first party view and it frequently contains a surprise about who already links to you. Then decide whether the question you have left is genuinely about somebody else. If it is, pay for one month.

On where links honestly come from when nobody is paying for them: free backlinks, and why the work is the part that is not free. On 21 October 2026 we read every link we could see on this site, 2,169 page bodies in all, against 2,082 live pages, and 935 of them, 44.9 percent, had no inbound link from any of those bodies. That figure is an upper bound rather than a count. No other page on this site links to the one above.

Questions about backlink tools

Which backlink tool has the biggest index?

Each vendor publishes its own figure and they are not measured the same way, so the counts are not directly comparable. Moz publishes over 40 trillion links. Compare the ceiling your tier gives you instead, because that is what you will actually read.

Can I check backlinks for free?

For your own site, yes and properly: Search Console plus the vendors' free checkers on properties you verify. For a competitor, only shallowly.

Is Domain Authority a Google metric?

No. It is Moz's own model. Google does not produce or use it, and the same is true of every equivalent score.

How many referring domains do I need?

There is no number. Compare the pages ranking for your query and look at which sites link to them, because the answer is relative to that one result page.

Do nofollow links count?

They are treated as hints rather than ignored, and they still bring people. Audit the mix rather than chasing a ratio.