Backlink Analysis
How well a site performs in search results depends largely on how many backlinks - external sites linking to it - exist for the site in question.
With both Ahrefs and Semrush, you can enter a domain name and see a list of all the backlinks to it that each tool can find.
According to data published by Ahrefs hong kong phone number list and Semrush, Semrush's domain database is significantly larger than Ahrefs', containing 808 million domains versus Ahrefs' 179 million (figures are correct at the time of writing).
This means that, in theory, Semrush should be able to provide a more comprehensive domain and backlink analysis.
Semrush Backlink Database Statistics (Accurate at time of writing)
Interestingly, however, in our own testing, the number of backlinks found by each tool seemed to vary quite a bit depending on the area we were looking at.
For example, doing a simple domain analysis, you might find that Ahrefs found more backlinks for Shopify than Semrush; but conversely, Semrush found more for Squarespace than Ahrefs.
Ahrefs Database Statistics
Backlink Reports and Tools
As for the backlink analysis itself, both Ahrefs and Semrush give you a LOT of useful information about the backlinks pointing to a domain, including a breakdown of:
number of dofollow vs nofollow links
country of origin of backlinks
anchor text used
new and lost domains
linking domain types (government, education, etc.)
I generally prefer the way Semrush presents this information - simple yet attractive graphs lay out the key statistics in a way that you can easily digest.