A natural referencing can be evaluated by a performance score.
The KPI which is the acronym of Key Performance Indicator means in French Indicator-Key Performance (KPI) of referencing.
It is a well-known term in SEO but is also used in the areas of website audience analysis, marketing and advertising.

In general, KPIs are used to assess the effectiveness of a system that has been put in place to achieve a particular goal, whether it be commercial, marketing, managerial or analytical.
This evaluation focuses on the positive and negative results produced by the implementation of a system such as community management, the online store and the customer relationship center.
A KPI can be the turnover, the number of orders received, the number of participants in an event, the number of clicks on a link, the number of visitors to a website, the market share etc.
We define a large number of KPIs for a given device and their monitoring is done on a dashboard.
In SEO, they are to be defined from the design of the positioning strategy because they are the ones who make it possible to see how it works and to define action plans or corrective actions.
The final objective of such an analysis and measurement tool is to obtain a return on the SEO work accomplished and therefore to know what and how to improve the positioning of a website on the search engines .
How in fact to know the effectiveness of the strategy put in place without the intervention of these KPIs?

Concretely,
SEO KPIs are indices such as the number of pages of the site indexed by a search engine, the number of Internet users visiting the site, the number of sessions, the number of pages opened, the number of new visitors, attendance the blog associated with the site, the duration of visits, the conversion rate, the number of inbound links, the number of likes, the number of followers, the number of fans, the number of shares on social networks, the bounce rate , page loading speed, positioning etc.
By taking a few of them, we can explain their roles and the actions they allow to be undertaken. To obtain the number of Internet users visiting the site, for example, a counter can be integrated into the site. An average of the visits as well as their evolution can be estimated after a few periods. A number considered insufficient makes it possible to decide to attract more visitors by publishing more interesting articles on the site for example. The inventory of the pages of the site indexed by Google makes it possible to know the proportion taken into account by the engine and therefore to carry out corrective actions such as improving the content for forgotten pages or also the submission of URLs.The number of links entering the site indicates the consideration that other sites have of you and it will also allow you to make contacts.
For these KPIs, simple and free tools as well as complete and paid tools are available on the Web.

Return on investment
The ultimate objective of practically any business's SEO strategy is to provide a return on investment. And whether it's an investment in an in-house team and resources or in an agency, it means seeing more money returned than you put in.
Tracking ROI from your SEO initiatives is critical since it is the best indicator of success – more money in the bank than you are spending. However, keep in mind that it might take time to realize a ROI, generally six to twelve months or more.
Know what your ROI objective is, and analyze your performance against it on a regular basis to understand and report on how it is progressing.
You may calculate ROI depending on your SEO spend and the income generated by the channel.

Transformations (Sales and Leads)
While a financial return is the overall KPI that many firms strive for, seeing results takes time. As a result, you should not rely just on ROI.
Measuring and tracking organic conversions (either revenue, leads, or both, depending on your company's setup) is a reliable approach to demonstrate performance. After all, a boost in organic conversions is directly traceable to your efforts.
Just make sure you know the conversion benchmark before you start working on a campaign; otherwise, it will be difficult to demonstrate the increase over what was previously created.
Take an average of conversions generated in the three months leading up to the start of your campaign and use it as a baseline for assessing growth.
In Google Analytics, you can measure conversions by setting objectives for lead conversions and using the eCommerce report to track sales by channel.

Returning to the notion that it takes time to get financial rewards from SEO, organic visibility is a strong KPI that you can follow and evaluate to show constant progress. And there are two methods to measure and report on this.
First, we'll look at the increase in impressions from Google Search Console.
This is an excellent technique to demonstrate continuing development in exposure, as impressions reflect the queries for which your site was visible, even if they did not result in clicks. Typically, this is due to an increase in ranking keywords that aren't in traffic generating positions (yet).
In any case, a rise in impressions indicates an increase in organic visibility and is a good indicator of future development.
You may also demonstrate an improvement in organic visibility by examining keyword trends in SEMrush's Organic Research tool, which shows how your visibility has changed for all indexed keywords, including those in lower places.

Organic Meetings
Increases in organic impressions should lead to an increase in organic sessions, and this is where you can begin to see the true impact of your SEO approach.
When your efforts begin to bear fruit, one of the major indicators you will notice is an increase in organic sessions (traffic).
Impressions lead to traffic, which leads to conversions; and when you look at it this way, witnessing a rise in organic sessions is when you actually start to realize an improvement in your SEO ROI.
Measuring organic sessions in Google Analytics is quite straightforward. However, for analyzing SEO KPIs, we recommend focusing on data from Google Search Console, since this allows you to remove brand searches and examine organic clicks for non-branded terms separately.
This is necessary to guarantee that your data is not distorted as a result of brand efforts that are creating an increase in branded searches.
To do so, navigate to the Performance report and click the +New icon at the top of the screen, where you may filter out your brand by selecting ‘Queries not containing.' Enter your brand name (and variants thereof) to discover how non-branded traffic performs.

While you should omit branded searches when analyzing the real impact of your efforts on organic traffic, a movement in the percentage split of non-branded traffic that your site receives is another crucial metric of success and growth.
Branded traffic is typically driven by prior awareness of a company or a suggestion from someone else. Perhaps a searcher has seen your social media advertisements, heard about your recent public relations effort, or even met you at an event. What's crucial to remember here is that the searcher was already aware of your existence.
While this certainly indicates that one marketing channel is performing well, it is unlikely to be traffic that can be directly attributed to your SEO efforts.
Non-branded traffic is typically generated by consumers looking for keywords related to your products or services that you score highly for. In other words, traffic from searchers who were presumably unfamiliar with your company before seeing you ranked on the SERPs.
You should also track the percentage of branded traffic vs non-branded traffic.

While keyword rankings may not be as crucial as some of the other metrics discussed above, they are certainly useful, and we highly advise you to monitor how your major target keywords rank on the SERPs.
If we go back even five years, rankings were pretty much the only way to gauge the performance of any SEO operation.
So, what has changed? Search using semantics.
Previously, most firms tracked a few of keywords and relied on them to determine the success of their strategy; but, today, a single page of content may rank for hundreds (often thousands) of distinct keywords.This means that different searchers may receive different results for the same query.

Tracking keyword rankings isn't exactly the gauge it once was, but it's still a great way to demonstrate progress. After all, watching your major keywords rise in rank indicates that your plan is beginning to bear fruit.

Backlinks are one of Google's top three ranking criteria, and there is no indication that this will change very soon. You must be aware of the present state of your link profile, both in terms of identifying any new connections you are earning and any difficulties with poisonous links that surface.
You should track the following link metrics:
Number of backlinks in total
Total number of domains pointing to this page
Number of broken links
The number of connections obtained
Toxic connections
However, because you are not viewing the data in context, these do not imply as much as they could. You should also compare your own link profile to that of your nearest competitors.

Although CTR (click-through-rate) is employed as a ranking criterion, the truth is that the higher your organic CTR, the more people will click on your SERP listing.
You should keep track of this on both a page and query level.
The greater the CTR, the better. CTR is a basic indicator that displays the percentage of individuals that click on your website after their search produces an impression.
When it comes to determining how relevant your title tag and meta description (the parts that appear in the SERPs) are to a specific query, organic CTR becomes quite significant.
When you compare your CTR to this, you'll instantly discover if you're outperforming the average or need to improve.
Under the performance report in Google Search Console, you may examine the CTR of your own sites and queries.

Bounce rate is an important metric for determining if your content engages visitors and may also be used to determine how relevant it is to the search queries for which it is ranking.
A high bounce rate indicates that the website isn't grabbing visitors' attention, resulting in missed possibilities to convert this traffic. And sometimes, tiny tweaks are all that is required to see a substantial difference, but if you are not documenting it on a regular basis, you may miss the chance.
In Google Analytics, go to Behavior > Site Content > All Pages to check your site's and pages' bounce rates.

A user's level of engagement increases the longer they spend on a page. And the more engaged a person is, the more likely they are to convert.
As a result, you should track your site's average time on page, both overall and on a page-by-page basis, and look for ways to improve it if you notice low durations.
Under Behavior > Site Content > All Pages in Google Analytics, you may track this.

Google Search Console, formerly known as ‘crawl errors,' helps you to investigate any coverage difficulties your site may have.
Typical examples include:
There are 5xx server problems.
There are 4xx errors.
Anomalies in crawling
Pages that aren't indexed
Crawled but not yet indexed
Discovered but not yet indexed
There is a duplicate, and the supplied URL has not been chosen as the canonical version.
Robots.txt has blocked this page.
In terms of tracking these difficulties as a KPI, keeping an eye on them on a frequent basis might help you stay on top of concerns that may indicate larger crawling or indexation issues.
While mistakes may not be a genuine measure of success, limiting them to a bare minimum should be one of your top priorities if you want to ensure that all of your pages that should be indexed are.
These may be seen in Google Search Console under Index > Coverage.

The speed of your website may have a detrimental influence on both your search results (and subsequent traffic) and your conversions, therefore it's important to pay attention to it.
We know what you're thinking: you've already spent time improving your site's PageSpeed score and everything is looking great. And that's fantastic. But when was it, exactly?
For a variety of reasons, these measures can fluctuate over time.
Perhaps someone on your editorial staff updated your blog post photos with new ones but failed to optimize them, resulting in high file sizes that cause these pages to load slowly?
Perhaps your server isn't operating as well as it was the last time you checked the performance of your site.
Because these factors might alter over time, it's important to keep a check on your site's speed.
You can simply stay on top of this with the SEMrush Site Audit tool, which allows you to execute frequent crawls (we recommend weekly) that will flag any sluggish pages.
You may look at the site performance report in particular to learn more about speed.
Instead of suffering as a result of slow page performance, you may address these issues as they arise.