Methodology · Visibility

How the Backlink share of voice and link gap is calculated

Method version visibility-v1 · Last updated 2026-10-13

In short

Backlink share of voice is a brand's share of the referring domains — unique websites linking to it — of all tracked brands together. The link gap lists important sites that link to at least one competitor but not to you, and linking-site traffic sums the monthly visits of the sites that link to each brand.

Formula

Backlink share of b = referring domains of b ÷ Σ referring domains of all tracked brands × 100
Link gap = sites with ≥ 1 link to a competitor and 0 links to you
Linking-site traffic of b = Σ monthly visits of the sites linking to b

How it is calculated, step by step

Collect each brand's referring domains, backlinks, domain rank and new and lost domains.
Divide each brand's referring domains by the total.
Cross the linking sites to find the link gap and sum their traffic per brand.

What goes into it

Referring domains: Unique domains with at least one link to the brand.
Linking-site rank and traffic: Authority (0–100) and estimated monthly visits of each linking site.

Data sources

Planned: DataForSEO Backlinks API and Labs traffic estimation. Until connected, labelled sample data.

How often it is updated

Monthly.

How to read it

Links from high-traffic, authoritative sites in your market matter most; the link gap is your outreach list.

Limitations

Link indexes are never complete; counts differ between providers.

Frequently asked questions

Why referring domains instead of backlinks?

One site can link thousands of times; counting unique sites reflects real reach better.

Keyword difficulty (KD) — How hard it is to reach Google's top 10 for a keyword, from 0 to 100: easy below 30, medium 30–59, hard 60 and above.
Share of voice (Visibility) — Your share of the visibility of all tracked brands together, per channel (SEO, GEO, backlinks, socials); the Visibility score is the average of the four.