Page Authority (PA) is a score from 1 to 100, created by the SEO software company Moz, that predicts how well a single web page is likely to rank in search results. It is the page-level companion to Domain Authority, which scores a whole website. Neither is a Google metric.
How Page Authority works
Moz runs its own crawler across the web and builds an index of links. For each page it looks at how many links point to it, how many separate websites those links come from, and how strong those linking pages are themselves. It then uses a machine learning model to turn that data into a single number, calibrated against how pages actually rank in search results.
A few things about the scale are worth knowing:
- It is logarithmic. Moving from 20 to 30 is far easier than moving from 60 to 70.
- It is relative. Scores shift when Moz updates its index or model, even if nothing changed on your site.
- It is based on Moz’s view of the web. If Moz has not discovered a link, it does not count.
Other tools have their own versions. Ahrefs, for example, calls its page-level score URL Rating. The numbers are not interchangeable, because each tool has a different crawler and a different model. See Ahrefs and Semrush for how the main suites compare.
Why it matters
Google does not use Page Authority. It has its own way of weighing links, descended from PageRank, and it does not publish the result. So PA can never cause a ranking change. What it offers is a quick, consistent way to compare pages using a proxy for link strength.
That has some practical uses. When you assess a link opportunity, the PA of the specific page that would link to you says more than the domain’s score, because a strong site can still have weak, unlinked pages. When you plan internal links, PA helps you spot the pages on your own site that have attracted the most outside links, which are good places to link from. And when you look at a competitor that outranks you, comparing PA alongside content quality can show whether links or relevance explain the gap.
Common mistakes
- Treating PA as a target. Chasing a higher number leads to buying or swapping links for the metric’s sake, which risks a Google penalty and does nothing for customers.
- Comparing scores across tools. A PA of 35 and a URL Rating of 35 do not mean the same thing.
- Reading too much into small changes. A drop of two or three points after a Moz update is noise, not a sign of trouble.
- Ignoring relevance. A link from a modest page on a respected UK trade association site can be worth more than one from a high-PA page that has nothing to do with your sector.
- Using PA for new pages. Fresh pages start low regardless of quality, so the score says little about them.
How to act on it
Use PA as one column in a spreadsheet, not as a verdict. When you review link prospects, combine it with relevance to your business, the real traffic the linking site gets and whether a human would ever click the link. When you audit your own site, sort pages by PA or by the number of linking domains to find your strongest pages, then check that they link on to the service and product pages you most need to rank.
If PA is low on an important page, the fix is the same as for any link weakness: create something worth citing, earn mentions from relevant UK sites, and route authority to it through internal links. That slow, relevance-first approach is how I run link building, and the third-party scores move as a side effect rather than as the goal.