If you compare prospect sites by their link metrics, you need to understand the measurements and collection changes behind the figures. Site Info reports a website's position in a link graph each month. It returns three measurements. Interpret the history using the collection rules and the January 2026 change described below.
Three measurements, always returned together
Every answer reports three levels for the site you asked about.
- Domain, the registrable domain, such as
example.com. - Host, the hostname you asked for, such as
example.comorblog.example.com. - www host, the www variant of that host.
All three appear because the host and its www variant are counted separately in the link graph, and their numbers do not agree. Neither one on its own is the complete answer for a site, and choosing one to display would hide the other.
Subdomains are kept distinct. blog.example.com and example.com are two different hosts with two different measurements, so a site whose content lives on a subdomain must be looked up by that subdomain.
How the www change affects the chart
This is the behavior worth understanding before reading any history chart.
From January 2026, the underlying web graph began counting www.example.com separately from example.com. For sites that serve from the www hostname, the bare host's score falls close to nothing from that month, and the www host's score increases.
The worked example is an anonymized host. Through December 2025 the host measured 56 and the www host measured 0. From January 2026 the host measures 31 and the www host measures 56, and every month afterward follows that pattern.
Nothing happened to the website. The measurement moved.
The history chart handles this by drawing one line: the bare host before that month, and the www host from it. That is deliberate, because what occurred was a move rather than a fall, and a chart showing a sharp drop would describe an event that did not happen.
Apply the same rule when comparing or exporting values across January 2026. Otherwise, www-served sites will appear to have declined sharply.
What the history covers
Measurements are monthly. Observations exist from 2017. Charts are drawn from January 2020, and anything older is dropped from the chart whether or not data exists for it.
A history is more useful than a current figure for the decision these reports usually support. A site holding steady, a site climbing for two years, and a site that peaked in 2022 and has declined since can all show the same number this month. They are three different prospects.
PRoT, and where it appears
PRoT stands for PageRank over Time. It is calculated by adding the PageRank values for every month held in the graph, producing one figure that describes how strong a site has been across the period rather than how strong it is now.
The product's own description is the clearest statement of what it is for: it asks for a domain that has been strong for a long time, not one that is strong only now.
Two sites can hold the same current PageRank and different PRoT values, because one has a longer or higher record behind it. PRoT on its own does not say which explanation applies, so read it alongside the monthly chart rather than instead of it.
Where PRoT appears differs by report. The Link Graph pages show PageRank only. Opportunity and brand page reports provide a minimum domain or host PRoT filter. Use it to select sites with a sustained record rather than a recent increase.
Batch lookups and the size limit
A batch lookup accepts up to 100 hostnames. A longer list is refused outright, with both counts named, and nothing in it is looked up.
The request is refused in full. Returning only the first hundred rows could leave you analyzing an incomplete list without noticing the missing results.
Paste one hostname per line or separate them with commas. A full URL is reduced to its host.
What the measurement supports, and what it does not
It supports comparing sites with one another, and comparing one site with its own past. Both are the questions a prospect list raises: is this site substantial, and how is it changing?
It does not establish that a link from that site will be valuable, that a search engine or AI assistant treats the site the same way, or that the site will accept a contribution. A link graph position describes the shape of links pointing at a host. It is evidence for a judgment, and the judgment stays yours.
It is also not a live figure. Measurements are monthly, so the current month reflects the most recent completed measurement rather than today.
Before using a chart to prioritize a prospect, check how its hosts and history were collected. Interpret the trend with those conditions in view.
See PageRank history, inspecting a prospect's history, or how current and historical measurements differ.