SEO explained
Reading a domain's authority over time
A single authority score tells you where a site stands today; its history tells you whether that standing was earned or bought. The shape of the curve is the more useful of the two, and it is what you should look at before buying a domain, accepting a guest post, or judging whether a competitor is actually gaining on you.
Why the trend beats the number
Two sites can both score 45. One climbed there over four years alongside rising traffic; the other jumped from 12 to 45 in a single quarter. The second is a link-buying signature, and the score will usually fall back once the vendor recrawls or the links are dropped.
The same reading works in reverse. A score sliding while content output continues normally often means referring domains are being lost — links rot as pages are rewritten and sites go offline, and a profile that is not being added to shrinks quietly.
What a sudden rise usually is
Bought links, an expired domain redirected in, or a single viral page that attracted a burst of coverage. The first two are risks you are inheriting; the third is real but rarely repeats.
The check that separates them: look at whether organic traffic moved with the score. Links that search engines count bring visitors. Links that only the tool counts move the score alone, and that gap is the tell.
How to see the history
No tool can show you a score from before it started measuring, so every history is bounded by when that vendor's index began. Rankizo's referring-domains report shows what a profile gained and lost over time, which is the data underneath any authority score and more diagnostic than the score itself.
The Wayback Machine is the other half of the job. If a domain's authority jumped, look at what the site actually was on that date — expired domains that were something else entirely are the most common explanation for a score that does not match the content.
Using it to judge a domain before you buy
Read the referring-domain curve, not the score. Steady accumulation is what a real site looks like. A vertical line followed by a plateau is what a private blog network looks like.
Then read the anchor text on the oldest links. A domain that used to be a pharmacy or a casino carries that history in its profile long after the content changed, and it is the thing most likely to make a rebuilt site fail to rank no matter what you publish.
Questions people ask
- Can I see a domain's authority from five years ago?
- Only if a tool was indexing it then, and only as far back as that vendor's history goes. Referring-domain counts over time are the closest proxy that is widely available, and they answer the same question.
- Why did my authority score drop without warning?
- Most often because referring domains were lost, or because the vendor changed its formula — every provider has recalibrated at some point, moving every site's score at once. Check whether competitors moved too before assuming it was you.
- Does buying an expired domain inherit its authority?
- Sometimes the score, rarely the rankings. Search engines reassess a domain when its content and purpose change, and the links that pointed at what it used to be stop counting for what it is now.
Tools that answer this on your own site
- Referring Domains
The domain-level roll-up, strongest sites first
- Domain Overview
One domain's traffic, keywords, competitors and links
Read the theory, then check your own site
The free plan opens every tool with 500 credits and no card, so you can look at your own numbers rather than an example.
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