Ahrefs vs DataForSEO: we ran both on the same 1,635 pages

We build a link outreach tool, which means we live and die by backlink data. Ahrefs has the best index in the business, and it charges like it. Their API starts at real money and climbs fast. DataForSEO sells similar looking data for cents. So we spent a few weeks and about $27 of DataForSEO credit finding out what the cheap data is actually worth, using our own production data as the measuring stick.

This is not a feature comparison. Every number below comes from running both APIs against the same real domains, the same real pages, and the same real outreach campaigns. Some of what we found surprised us. One finding made us turn off a filter we had trusted for months.

First question: how much backlink data do you actually get back?

Take one domain, ask both APIs the same question: how many websites link to it? Here are five real small sites from our tests, counting live, followed links, deduplicated to one per domain, which is the only counting method that matters for outreach.

The pattern held everywhere we looked: DataForSEO finds roughly a third to a half of the referring domains Ahrefs finds, once you count honestly. And here is the trap for anyone comparing the two: DataForSEO's headline totals often look BIGGER than Ahrefs. For one domain it reported 21,765 referring domains where Ahrefs showed 9,689. The difference is dead and historical links. Filter both sides down to live links and the picture flips. Totals are marketing. Filtered rows are reality.

Coverage also gets worse as sites get bigger and more commercial. We took 30 hand-verified prospects for a mid sized e-commerce brand, all of them present in Ahrefs, and checked how many existed anywhere in DataForSEO's index. Nine. The other 21 simply are not there. For small niche sites the gap is much kinder, which tells you exactly who the cheap index is for.

The traffic numbers are on different planets, and that is fine

Both tools estimate how many monthly visitors a site gets from Google. Neither one is measuring anything. They are both models built on keyword rankings, and the models disagree wildly. Across 339 domains where we had both numbers, DataForSEO's estimate ran 7.3x higher than Ahrefs at the median. But the median hides the chaos: the middle half of sites ranged from 2.5x to 21x, and one in ten sites was off by more than 60x.

So converting between them with a fixed factor is a lie you tell yourself. What actually holds up is the ordering. When DataForSEO says site A gets more traffic than site B, Ahrefs almost always agrees (rank correlation around 0.89). Use either scale on its own terms and never mix them in one spreadsheet.

The page traffic cross-match

This was the test we cared about most. In outreach, the single nicest signal a linking page can have is real visitors of its own. So we took 1,635 referring pages from our own past campaigns, where we had recorded Ahrefs page traffic at pull time, and asked DataForSEO about the exact same URLs.

As a yes or no signal, the two providers mostly agree. As a number, forget it. One page showed 1,700 monthly visits on Ahrefs and 6 on DataForSEO. Another showed 1,215 on Ahrefs and 5,018 on DataForSEO. Same pages, same month, both tools confidently wrong in opposite directions.

The disagreements taught us something too. One blog post about Goodwill outlet stores showed zero on Ahrefs when we originally pulled it, and 178 on DataForSEO today. Sounds like DataForSEO hallucinating, right? We pulled the page's actual keyword rankings to check. It currently ranks 68th for a keyword searched 60,500 times a month. It gained rankings in the months since our original pull. The estimate was not wrong, our snapshot was old.

That check, by the way, costs about 1.3 cents per page and returns the receipts: which keywords, what position, worth how many visits. An estimate you can audit beats a bigger estimate you have to trust.

Here are real rows from the cross-match so you can see the disagreement with your own eyes. Same domain, both providers, side by side.

The spam score that deletes TV stations

DataForSEO assigns every domain a spam score from 0 to 100, and their API happily filters your results by it server side. We ran every pull with "spam score under 30" for weeks. It seemed prudent.

Then we tested it against 1,495 domains that we knew were good, because they came from our own vetted campaigns, including 292 domains we had actually emailed. The filter would have silently deleted 22% of them. Among the casualties: three real local TV news stations, a university newspaper, and austin.com. Sites a human would kill to get a link from, scored as spam.

The score is not useless though. It just needs a second witness. High spam score AND zero search traffic together flagged only real junk in our data: link farms, dead review sites, .shop and .today domains nobody has visited. That combination had zero false positives among every domain we had ever emailed. The lesson generalizes: never let a data provider pre-censor your results on one signal. Pull everything, then judge with signals that corroborate each other.

What actually predicts a dead page

We also physically visited about 700 of the pages DataForSEO returned, sampled across traffic levels, to see which ones still existed. The result is the clearest chart of the whole study.

Traffic predicts life. A site with no measurable search traffic had a nearly one in four chance of the page being gone entirely. Above a thousand monthly visitors, dead pages almost disappear. Meanwhile the authority score, DataForSEO's version of domain rating, predicted almost nothing: pages were alive at roughly the same rate whether the domain scored 5 or 55. If you filter cheap backlink data, filter on traffic, not authority.

So what should you expect if you build on DataForSEO?

Here is the honest summary we wrote for ourselves. A typical competitor pull on a small niche site costs 30 to 60 cents, returns a few hundred raw rows, and after cleaning yields roughly 100 usable outreach leads. Against Ahrefs you will see a third to a half of the referring domains, and on bigger commercial sites the gap widens to the point where whole prospect sets just are not in the index. The traffic estimates are directionally sound, inflated in absolute terms, and occasionally wrong by an order of magnitude in either direction. The spam score is dangerous alone and useful with a second witness.

Whether that is a good deal depends entirely on what a lead is worth to you. Ahrefs remains the better index, clearly. But an Ahrefs API bill starts around what many small teams pay for all their tooling combined, and DataForSEO delivered a hundred real, live, filterable leads per competitor for the price of a coffee refill. For small site outreach, where the pool is small blogs Ahrefs and DataForSEO both see reasonably well, the cheap index earns its keep. For enterprise competitive analysis, it does not pretend to compete.

We ended up building for both: DataForSEO as the built in data source that works the moment you sign up, Ahrefs as the bring your own key upgrade for people who already pay for it. The tests above are why.

Methods, for the skeptics

All tests ran in July and August 2026. Backlink pulls used live, followed, one link per domain counting on both sides. The page traffic cross-match compared Ahrefs numbers recorded at original pull time against DataForSEO lookups made in August, so some disagreement is honest drift over time, which is exactly how the Goodwill outlet page fooled us. The known good domain set came from five real outreach projects. Liveness was tested with real HTTP requests, two attempts, following redirects, treating hard 404s, dead DNS, and broken SSL as dead. Traffic estimates from every SEO tool, including Ahrefs, are models of search rankings, not analytics. Nobody can see a page's newsletter or social traffic, so zero means zero measurable search traffic, not zero readers.