Ahrefs vs Majestic for anchor distribution: the index bias problem

Ahrefs vs Majestic for anchor distribution: the index bias problem

When auditing an anchor profile, the tool you choose shapes the conclusion. Ahrefs and Majestic do not see the same web, and that divergence matters for ratio work.

Majestic's anchor cloud derives from its Historic Index, which retains links long after they vanish. This inflates the apparent count of older, often exact-match anchors built years ago. Ahrefs prunes dead links more aggressively, so its live anchor breakdown skews toward what is currently active.

The practical consequence: a profile that looks 18% exact-match in Ahrefs may read 26% in Majestic, purely from index methodology, not from any real-world difference.

On one hand, Majestic's persistence is useful for forensic Penguin-era audits where you want to know what Google once saw. On the other, Ahrefs better approximates the live graph a crawler re-evaluates today.

Limitation: neither vendor publishes crawl-frequency-by-tier, so we cannot fully reconstruct sampling bias. Treat both numbers as estimates bracketing a true value you cannot observe directly.

My working rule: use Ahrefs for current-state ratio decisions, Majestic for historical reconstruction. Never compare an exact-match percentage across the two tools as if they measure the same thing — they measure different indexes.

Open question: does anyone have a paired dataset measuring how far Ahrefs and Majestic exact-match ratios diverge across, say, 500 domains? That delta is, to my knowledge, undocumented at scale.