Ahrefs is an SEO toolset whose value rests on infrastructure most competitors do not have: its own web crawler, which indexes an enormous number of pages continuously. Everything else in the product is a view onto that index. When you look up a domain's backlinks, you are querying a crawl the company built itself rather than a licensed dataset, and the freshness and coverage of that crawl is the reason the tool costs what it does.
Site Explorer is the part people buy it for. Enter any domain or URL and you get its backlink profile, the referring domains, the anchor text distribution, which links were gained and lost recently, the pages attracting the most links, and estimated organic traffic broken down by keyword. Pointed at a competitor, it is a reasonably direct readout of their strategy: what they rank for, which pages earn links, and where the traffic actually comes from rather than where they claim it does.
Keywords Explorer provides volume, difficulty, clicks and parent topic for keyword ideas across several search engines, with the clicks metric being a useful corrective to raw volume, since a large share of searches now end without anyone clicking a result. Site Audit crawls your own site and reports the technical problems that suppress rankings. Rank Tracker follows positions over time across locations and devices. Content Explorer searches published pages by topic and performance, which is how people find what has already earned links in a subject area.
The objection is price. Ahrefs is expensive, there is no meaningful free tier, and the credit system limits how many reports you can run per month, so heavy research days exhaust an allowance. Webmasters can verify their own site for a free limited view, which is genuinely useful but not a substitute. The interface assumes you already know what a referring domain or a canonical is, so it is not a first SEO tool.
It is worth remembering that every traffic and difficulty number here is a model, not a measurement. Treat them as comparative rather than absolute: useful for ranking one opportunity against another, misleading if quoted as fact.
Who it suits: agencies, in-house SEO teams and serious content operations where the subscription is a fraction of the value of one good decision. Who should look elsewhere: individuals and early startups, for whom the cost is hard to justify.