Link building tools: the best tools for each step of the job

At a glance

• Most link building work needs one backlink research suite (Ahrefs or Semrush), Google Search Console, and an outreach tool if you pitch at scale.
• Ahrefs, Semrush, Majestic and Moz all crawl the web and score sites with their own metrics, and none of those metrics comes from Google.
• Google Search Console and Ahrefs’ free plan for verified sites cover your own backlinks at no cost, but you need a paid suite to research other sites.
• Automatic backlink software mass-produces low-quality links and doesn’t belong anywhere near a site you care about.
• If you build links on sites you own, the stack becomes a domain finder, a backlink checker, the Wayback Machine and hosting for the network.

Tool	Job	Free option	Best for
Ahrefs	Backlink research, prospecting, broken links	Free plan for your verified sites	Anyone who pays for one suite
Semrush	Backlink research, competitor gaps	Free backlink checker	SEOs who also run keyword and PPC work
Majestic	Link graph, Trust Flow and Citation Flow	Free account with a few Site Explorer lookups a day	Vetting expired domains
Moz	Link Explorer, Domain Authority	Free Moz Pro trial, or a free account with limited Link Explorer access	Teams that already report in DA
Google Search Console	Your own site’s links	Free	Every site owner
Google search operators	Finding prospects	Free	Small, targeted campaigns
Hunter	Finding email addresses	Free plan, 50 credits a month	Outreach
BuzzStream	Outreach CRM	Free trial	Small teams
Pitchbox	Outreach at agency scale	Free trial after a demo call	Agencies
ChatGPT	Drafting personal first lines	See ChatGPT pricing	Anyone writing pitches
Screaming Frog SEO Spider	Crawling for broken links	Free version, up to 500 URLs per crawl	Broken link building
Wayback Machine	Seeing what a dead page held	Free	Broken links and expired domains
SEO Domain Finder	Finding auction and closeout domains	7-day trial	Building your own network
Easy Blog Networks	Hosting and maintaining your own blogs	7-day trial	Running a network

The free options for Majestic, Moz, Hunter, BuzzStream, Pitchbox and Screaming Frog are from each vendor’s pricing or free-tools page, fetched 2026-10-28. Free tiers change often, so check again before you plan around one.

Backlink research: the four index tools

These tools run their own crawlers, store the links they find, and let you look up any site’s backlinks. Everything else in link building starts here: finding who links to competitors, checking a prospect’s quality, and watching your own profile.

One thing to keep straight before you compare them: Domain Rating, Authority Score, Trust Flow and Domain Authority are each vendor’s own estimate. Google doesn’t use any of them. They are useful for comparing sites inside one tool, and much less useful compared across tools.

Ahrefs

Ahrefs is the tool most link builders reach for first. Site Explorer shows any site’s backlinks and referring domains, Link Intersect shows sites that link to your competitors but not to you, and Content Explorer finds pages on a topic along with who links to them. Its main site metric is Domain Rating (DR).

On index size, Ahrefs lists 285 million domains and 35 trillion historical external backlink records, and says its backlink index is “updated with fresh data every 15 minutes” (per Ahrefs, fetched 2026-10-28). For your own sites, Ahrefs Free gives “Free website analytics, technical audit & SEO metrics for your verified websites”, including Site Explorer’s view of who links to you (per Ahrefs, fetched 2026-10-28).

Verdict: if you only pay for one research tool, pay for Ahrefs or Semrush, and Ahrefs has the edge for link-specific work like Link Intersect and broken backlinks.

Semrush

Semrush is a full marketing suite with strong backlink tools inside it. Backlink Analytics shows any domain’s link profile, and Backlink Gap compares several domains to find sites that link to your competitors and not to you. Semrush states its index holds “more than 43 trillion backlinks” and 390 million referring domains, and it offers a free backlink checker you can use without an account (per Semrush, fetched 2026-10-28).

Verdict: pick Semrush over Ahrefs if you also need its keyword, PPC and content tools in the same subscription. Semrush is a tool, not a link building service: it shows you opportunities, it doesn’t place links.

Majestic

Majestic does links and only links. Its two metrics are the ones many expired-domain buyers still check first. Majestic defines Trust Flow as “a score based on quality, on a scale between 0-100”, built from distance to a set of manually reviewed trusted seed sites, and Citation Flow as a 0 to 100 score measuring “the link equity or ‘power’ the website or link carries” (per Majestic, fetched 2026-10-28). Topical Trust Flow breaks the score down by subject, which helps you check whether a domain’s links come from your niche.

Verdict: a good second opinion next to Ahrefs or Semrush, and the standard check when you vet domains.

Moz

Moz’s Link Explorer shows backlinks and the Domain Authority (DA) score. Moz describes DA as a score from 1 to 100 that predicts how likely a site is to rank compared to its competitors, and says it is not a Google ranking factor (per Moz, fetched 2026-10-28). DA is widely quoted, so you will meet it in sales pitches and client reports. Moz Pro has a free trial, and a free Moz account gives limited access to Link Explorer, Keyword Explorer and the MozBar toolbar (per Moz, fetched 2026-10-28).

Verdict: useful if your team or clients already speak in DA. Otherwise one of the two big suites covers the same ground.

The free baseline

Google Search Console

Search Console’s Links report is the only link data that comes from Google itself. It shows your top linked pages, top linking sites and top linking text. It covers only sites you have verified, and Google says the report “isn’t a comprehensive list of every link on your site” but “shows a sample of internal and external links” (per Google Search Console Help, fetched 2026-10-28). Use it to see which links Google knows about, and a paid suite for everything else.

Free tiers of the big suites

Between Search Console, Ahrefs Free for your verified sites and Semrush’s free backlink checker, you can watch your own profile and spot-check a competitor without paying. What the free options don’t give you is research at scale: exporting thousands of a competitor’s links, running Link Intersect, or filtering prospects. That is where the subscription earns its fee.

Prospecting and finding contacts

Ahrefs Content Explorer and Semrush

The best prospects are sites that already link to pages like yours. In Ahrefs, search Content Explorer for your topic and sort by referring domains. In Semrush, run Backlink Gap against two or three competitors. Either gives you a list of sites that have shown they link out on your subject.

Google search operators

For a small, targeted campaign, plain Google searches still work: "your topic" inurl:resources, "your topic" intitle:"useful links", or "your brand" -site:yourdomain.com to find unlinked mentions. It is slow, but it costs nothing and finds sites the indexes miss.

Hunter

Hunter finds the email addresses linked to a domain and checks whether a given address is likely to deliver. It is the usual step between “this site would be a good fit” and an outreach email. Hunter’s free plan includes 50 credits a month. Finding an email costs 1 credit and verifying one costs half a credit (per Hunter, fetched 2026-10-28).

Outreach and relationship tracking

BuzzStream

BuzzStream is an outreach CRM: it stores your prospects, finds contact details, sends and tracks emails and keeps the conversation history in one place, so two people on a team don’t pitch the same editor twice. It suits small teams and freelancers. BuzzStream offers a free trial, and lists its Starter plan for solo users at $49 a month (per BuzzStream, fetched 2026-10-28).

Pitchbox

Pitchbox covers the same job for agencies running many campaigns at once, with prospecting, sequences and follow-ups at a larger scale. If you send a few dozen pitches a month, it is more than you need. Pitchbox says free trials are available to teams, arranged through a demo with its product specialists (per Pitchbox, fetched 2026-10-28).

ChatGPT

ChatGPT is good for drafting a personal first line from the prospect’s own article, or tightening a pitch you already wrote. It is bad at mass templates: editors recognize them and delete them. Write the request in your own words and let the tool help with the opening. For wording that gets replies, see our guide to outreach email templates.

Broken link building

Ahrefs broken backlinks report

Enter a competitor or a resource page in Site Explorer and open the broken backlinks report: it lists links pointing at pages that now return 404. Every one is a site that wanted to link to that content and now links to nothing.

Screaming Frog SEO Spider

Screaming Frog crawls a site the way a search engine does and lists every broken outbound link. Crawl a resource page or a whole niche site, filter for broken external links, and you have a list of replacement opportunities. The SEO Spider is free for crawls of up to 500 URLs. A licence lifts that limit and adds advanced features, at £199 per user per year (per Screaming Frog, fetched 2026-10-28).

Wayback Machine

Before you pitch your page as a replacement, look up the dead URL on the Wayback Machine to see what it held. Your page has to cover the same thing, or the editor has no reason to swap the link.

Monitoring and audits

Once links exist, you need to know when they disappear and whether anything harmful has appeared. Search Console shows what Google sees. Ahrefs and Semrush both send alerts for new and lost backlinks and include audit reports that flag suspicious links. For the method, see how to check any site’s backlinks.

Tools for links you own

Every tool above helps you get links on other people’s sites. The other route is to build them on sites you control. Our PBN guide makes the case: with your own sites, “you don’t just control where the backlinks point, you also control other related signals, such as anchor text and the topical relevance of the link source.” That route has its own stack.

SEO Domain Finder

SEO Domain Finder is our tool for browsing auction and closeout domains. It scrapes registrars and lists domains you can filter by your requirements. For other ways to find domains, see our roundup of expired domain finders.

Ahrefs and Majestic for vetting

Before buying, check the domain’s link profile. Our PBN guide sets a floor of at least 10 Ahrefs Domain Rating and 10 or more referring domains, and a clean anchor text profile with nothing from pharma, adult or gambling sites. Majestic’s Topical Trust Flow tells you whether the links match your niche.

Wayback Machine for restoring content

The Wayback Machine shows what the domain used to publish. Restoring the old pages that still have links pointing at them keeps much of the authority the domain built.

Easy Blog Networks for hosting

A network needs each blog on separate hosting so the sites don’t share an obvious connection. Host your own network on Easy Blog Networks: every blog gets a unique IP at a large hosting provider with that provider’s own nameservers, WordPress updates run automatically, backups are taken daily, and AI articles can be posted on a schedule using your own OpenAI API key. Plans start at US$39/month for 10 blogs (excluding tax), with a 7-day free trial.

What about automatic backlink software?

A whole category of tools promises links on autopilot. They create profiles, blog comments, forum posts and free “web 2.0” blogs by the thousand, each with a link to your site. We aren’t naming them, because none of them belongs pointed at a site you care about.

The links they create sit on spam pages that nobody reads. Google’s spam policies list “Using automated programs or services to create links to your site” as an example of link spam (developers.google.com, fetched 2026-10-28). The result looks like a link farm from the outside, because that is what it builds. Some SEOs point automated links at their other backlinks rather than at the money site, a tactic covered in our separate guide to tiered link building.

Which tools you need: three starter stacks

A starter stack for a single site or a small client list: Google Search Console, one paid suite (Ahrefs or Semrush), an email finder such as Hunter, and a spreadsheet for outreach. Add the Wayback Machine for broken link work.

An agency stack: Ahrefs and Semrush (many agencies keep both because clients ask for each), Majestic for vetting, an outreach CRM such as BuzzStream or Pitchbox, Screaming Frog for crawling, and Search Console access for every client.

A network-builder stack: SEO Domain Finder, Ahrefs or Majestic to vet domains, the Wayback Machine to restore them, and Easy Blog Networks to host and maintain them.

For how these tools fit into a plan, see our guide to link building strategies.

FAQ

What is the best free link building tool?

Google Search Console, because it is the only one with Google’s own link data. Pair it with Ahrefs Free for your verified sites. Neither will research other sites at scale.

Do I need both Ahrefs and Semrush?

Not usually. They overlap on most link work. Pick Ahrefs if links are the main job, Semrush if you also need its keyword and advertising tools. Agencies often keep both because different clients report in different metrics.

What is the best tool for outreach?

Hunter to find the address and BuzzStream to manage the conversations, for most teams. Agencies running many campaigns at once tend to move to Pitchbox.

Does automatic backlink software work?

Not for the site the links point at. It produces large numbers of links on spam pages, which Google’s spam policies name as link spam and which carry little or no value.

Is link building still relevant?

Yes. Our PBN guide’s view is that when everyone publishes similar optimized content, links are what decide who reaches the first page. The tools change, the need for links doesn’t.