Semrush vs Ahrefs vs Moz: the three suites, side by side

• Pick Ahrefs if your next quarter is about links and rivals: its backlink index and Site Explorer are what it is known for.
• Pick Semrush if you want one place for keywords, tracking, audits and the marketing work around them, including advertising data.
• Pick Moz if you are learning as you go and want a smaller surface with strong teaching behind it.
• Pick none of them yet if your site has a handful of pages and no content plan: Search Console and a crawler will tell you more this month.

Feature lists are long and mostly overlapping. Five questions separate the three in practice.

• The link index: whose crawl finds the links, and how well the explorer lets you read a rival's profile.
• Keyword data: how the ideas are grouped, how the difficulty is modelled, how many markets are covered.
• The audit: what the crawler finds on your own site and how it explains it.
• Rank tracking: how many queries, how often, and whether rivals are tracked beside you.
• The learning curve: how long before the tool answers a question you actually had.

Ahrefs: the link work. Site Explorer is the cleanest way to read who links to a rival, from which page and with what anchor, and Content Explorer turns that into a list of people who write about your subject. If your plan is to earn links this quarter, this is the one that pays for itself first.

Semrush: the breadth. Keyword Magic Tool for the ideas, Position Tracking for the watch list, Site Audit for the technical debt, Backlink Analytics for the links, and modules that go past SEO into advertising and content. If one subscription has to cover a whole marketing job, it is this one.

Moz: the teaching. Domain Authority became a shared vocabulary because Moz explained it for years, and the tools are smaller and easier to learn. If you are the founder doing this yourself between two other jobs, less surface is a feature.

Each suite scores a domain out of 100 from its own link index with its own model. The numbers look comparable and are not.

• Domain Rating is Ahrefs's, built from its backlink index.
• Authority Score is Semrush's, built from link data, its traffic estimate and spam signals.
• Domain Authority is Moz's, relative and logarithmic, so moving from 20 to 30 is easier than 70 to 80.
• Google uses none of them. Its representatives have said there is no single site-wide authority score in its systems.

Use whichever your tool gives you to compare two sites inside that tool, on the same day. Never as a target, and never across tools.

Founders buy a suite for the whole thing and use four screens. Those four, in the order they matter.

• The keyword explorer, once, to size the twenty searches worth writing for.
• The link explorer on two rivals, once a quarter, to build a list of places that might link to you too.
• The site audit, once after a big change, and then rarely.
• The rank tracker, weekly, for the ten queries that pay.

That is a few hours a month of use. It is worth a subscription when the site has a content plan and enough pages to audit. Before that, the same hours in Search Console tell you more, because they are about your site rather than a model of it.

• Google Search Console: your real impressions, clicks, positions and indexing. The only figures that are Google's own.
• Bing Webmaster Tools: free keyword research with volumes, and a backlink comparison against another domain.
• Ahrefs Webmaster Tools: Site Audit and Site Explorer, free on sites you have verified.
• The MozBar extension: a page's metrics at a glance while you read a results page.
• A desktop crawler's free tier: the technical facts about your own site, up to a few hundred URLs.

That set answers most of what a site under a hundred pages needs. The paid suites earn their place when you need rivals, volumes at scale and history.

1. 1

   Write your five questions first

   For example: which searches can this site realistically win, who links to my two closest rivals, what is technically broken, which ten queries do I want tracked, and what did they publish last month.

2. 2

   Answer them in the tool, not in the tour

   Ignore the dashboard. Go straight to the screens that answer your questions and time how long each takes.

3. 3

   Check a domain you know well

   Your own site, or a rival you have studied. The tool whose picture matches what you already know is the one whose data you can act on.

4. 4

   Export something

   You will live in spreadsheets more than in the interface. A tool whose export is awkward is a tool you will stop opening.

5. 5

   Decide before the trial ends

   If none of the five questions was answered faster than Search Console could, keep the money and revisit in a quarter.