What Is SEMrush? Everything You Need To Know – 2022

What’s Semrush and which features work best for tracking and improving your search rankings? Here’s everything you need to know.

Research on keywords, evaluation of competitors, site audits, traffic statistics, and link building. These are only a few of the areas you need to focus on when developing an effective SEO strategy for your business.

Although SEO can be confusing and challenging to comprehend, it is still one of the best strategies to increase traffic to your website and raise its search rating.

However, if you don’t have the appropriate digital marketing tools available to you, going through the various research and analysis processes may become much more difficult.

Semrush can help in these circumstances.

Semrush is now among the most widely used SEO tools for businesses that need assistance with website optimization for search engines and managing digital marketing initiatives.

Do the software’s sophisticated features and analytics seem a little difficult to understand? Please don’t worry; we will cover everything you need to know about Semrush and how to use it to advance your SEO tactics.

What Is SEMrush and How Does It Work?

Semrush is a well-known SEO tool for performing competitor research, optimizing Google Ads, and conducting keyword research.

It is an all-in-one marketing reporting tool made to help digital marketers in improving the organic search traffic to their websites. Additionally, you may assess your position in relation to your rivals and improve your data-driven selections regarding the keywords to target for both organic search and Google ad campaigns.

Semrush is used by several well-known companies, such as Booking.com, Quora, HP, and eBay.

With the use of this advanced SEO tool, you can easily spot patterns and trends in your particular sector. This will enable you to evaluate your on-page SEO and pinpoint the regions that require optimization for more effective lead production.

Semrush is one of the top tools for keyword research as well. You will get an understanding of the keywords that your rivals are using and how they are performing. It will be considerably simpler for you to stay ahead of your competition and keep up with the most recent trends as a result of the generous amount of data you receive.

Due to its wide range of advanced capabilities, Semrush is utilized by some of the greatest internet marketers in the world, but it is also ideal for beginners. The platform is simple to use, and Semrush greatly simplifies SEO even for those with no SEO knowledge.

In conclusion, Semrush functions by offering users a wealth of data that can be utilized for:

• Improving your website’s overall performance
• Monitoring the most used search terms on Google
• Creating content with a high probability of increasing traffic
• Identifying new link-building opportunities
• Improving your website’s technical aspects for improved search engine positioning

Is Semrush a Free Tool?

There is a free version of Semrush, however, it offers few features and services. You can accomplish the following with a free account:

• Develop and run a single Semrush project
• 10 daily questions about keyword and competitor research
• Keyword monitoring (limited to 10 keywords)
• Go through all 100 pages of your website.

The free edition doesn’t offer nearly as much flexibility and advantages as the paid version, despite the fact that these capabilities can be helpful for beginners in digital marketing.

The free edition doesn’t offer nearly as much flexibility and advantages as the paid version, despite the fact that these capabilities can be helpful for beginners in digital marketing.

There is a 14-day free trial available to try out Semrush if you’re not sure whether you should sign up for their service. Paid plans cost between $119.95 and $449.95 per month, or between $99.95 and $374.95 per month if you subscribe for a full year.

In addition, they provide an enterprise package for large firms that demand more adaptability and personalization.

What Is the Difference Between Semrush and Google Analytics?

The two analytics programs that internet marketers use the most right now are Semrush and Google Analytics. These two provide two entirely different sorts of services, albeit sharing some aspects.

The primary distinction between both is that while Semrush switches the emphasis to external data and examines your competitor’s website, Google Analytics is used by marketers to study the internal data on their own websites.

Since it is impossible to obtain the internal data of a competitor’s website, the information you receive from Semrush is essentially the next best thing.

PRO TIP: How to Monitor and Evaluate Your SEO Performance

There are a number of on-page events and metrics you can track from Google Analytics and Google Search Console that will help you understand how your visitors are reacting on your landing pages:

• organic landing page sessions. Which landing pages lead to the most signups and organic traffic?
• landing page organic goal completions. Which landing pages convert well and which require updating or enhancing?
• organic clicks from queries. What search terms send the most visitors to your website?
• single page, organic clicks. Which pages on search results pages get the most clicks?
• Organic sessions How many visits to your website are from organic search engines?

And more…

What Is the Difference Between Semrush and Ahrefs?

Ahrefs is significantly more comparable to Semrush than Google Analytics, as both are SEO research tools that concentrate on the external components of rival websites.

Both of these products now provide a largely comparable range of features and services, but this wasn’t always the case. Ahrefs was just recognized a few years ago as a backlink analysis tool. Ahrefs is now a legitimate rival in the SEO research market thanks to the company’s decision to offer a tonne of new capabilities in the meantime.

Semrush and Ahrefs differ mostly in the metrics they focus on. Semrush is the best choice, for instance, if your main focus will be on researching keywords and assessing the technical aspects of SEO (such as the health of your website).

On the other side, digital marketers who invest more time in link building and looking for backlink prospects will benefit more from Ahrefs.

Read more: What is SEMRush rank? – Guide for how it works?

Most Powerful Semrush Features for Improving Your Search Rankings

We can discuss the various elements that you may utilize to raise your overall search rankings now that you understand what Semrush is and how it functions.

Semrush offers users dozens of capabilities, but if you are unfamiliar with the software, it may be difficult to choose the finest ones.

We came up with a list of those that stand out as the most effective for improving search ranking after interacting with some of the top digital marketers in the field and completing our extensive research.

1. Position Tracking
2. On-Page SEO Checker
3. SEO Content Template
4. Organic Traffic Insights
5. Site Audit
6. Keyword Magic Tool
7. Keyword Gap Analysis
8. Keyword Overview
9. Keyword Alert
10. Keyword Tagging
11. Domain Overview
12. Traffic Analytics
13. Link Building
14. Project Dashboard

Position Tracking

Most people agree that Semrush’s most powerful feature is position monitoring. It can be used to monitor a website’s daily rankings based on a specific set of target keywords. You will gather the information required to evaluate the effectiveness of SEO and PPC campaigns using the various reports (tagging, sorting, filtering, exporting, etc.).

The following are some of the main benefits of position tracking:

• Tracking of keywords and domains
• Comparisons of locations on a map
• Types of project devices
• Finding nearby competitors and monitoring their SEO
• Reports from Featured Snippet (great for finding featured snippet opportunities)

Position Tracking is one of Semrush’s most effective capabilities for boosting search ranks, according to Sophie Burke of Bead the Change. You may use this to track your positions for any term, find nearby rivals, and tag your keywords.

On-Page SEO Checker

The On-Page SEO Checker function gives customers a list of actions they may take to improve the search rankings of the pages on their website. This list includes suggested keywords, suggestions for improving on-page SEO, the likelihood of backlinks, the ideal length of the material, and much more.

These suggestions are all based on the target keyword research of the top live rivals in your niche.

No tool is more crucial for increasing ranks than the On-Page SEO Checker tool, according to Jakub Rudnik of Shortlister. The most efficient strategy to raise rankings is to produce the best content that is also the best-optimized material. It’s essential to get a comparison of your pages to those of your rivals along with suggestions for improving your content.

SEO Content Template

For content writers who need a little assistance producing SEO content, this function is fantastic. It creates a template based on an analysis of the target keywords and offers recommendations for what to add.

Semrush will automatically provide a template for writing SEO-friendly content after you enter a specific keyword.

The following are some of the elements in the template:

• Text size suggestions
• overview of readability
• Supporting word recommendations
• Potential changes for backlinks
• insight into the target keywords being used by your competitors and where they are employing them

“I found their Semrush’s SEO Content Template to be a particularly helpful tool for analyzing how competitive a topic is, discovering appropriate subtopics and semantic keywords to cover, and finding the average word counts of the current top 10 ranked sites,” adds Eric Hoppe of Crowd Content. The likelihood that your content will rank well increases if you can use this information when writing it.

Organic Traffic Insights

According to Sam Thomas of Embryo Digital, “The Organic Traffic Insights tool is amazing for spotting quick-win chances.” “Outside of your primary keyword emphasis areas, you can locate low-hanging fruit that is already generating modest traffic, but with a little concentration, could significantly improve the total search rankings of a website with fewer resources than the traditional high competition keywords. Although both are crucial, the client has won out nicely.

Users may get a thorough dashboard with the help of the Organic Traffic Insights feature, which pulls information from your Google Search Console, Google Analytics, and Semrush accounts.

Site Audit

Using Semrush’s Site Audit tool is one of the finest ways to determine an estimate of the health of your website.

This function gives you a list of issues that are categorized and indicates where your website is doing poorly. You will improve your website’s SEO effectiveness if you address the concerns on the list.

Everything from duplicate content and broken links to crawl ability and HTTPS implementation is included in the technical study.

Here is one of the quotes we gathered from the top digital marketers to demonstrate the significance of the Site Audit tool.

The site auditing tool is one of the most crucial things that my team relies on at ProLightingRental.com, according to Will C of the eCommerce store for event light rentals. For websites with a lot of specialized coding and unique infrastructure, this tool is amazing. When you add a new feature or even patch an existing bug, a complicated codebase may experience a variety of problems.

The SEO of your website may be negatively impacted by many of these problems. So, following each deployment, I use the site auditing functionality feature to check that no SEO-related infrastructure, including but not limited to content, layout, canonicals, and metadata, has been harmed. I’ve discovered problems and, as a result, minimized any SEO effects from deployments that weren’t thoroughly tested on numerous occasions.

Keyword Magic Tool

The most used Semrush tool for keyword research is definitely the Keyword Magic Tool. It allows you to track semantically related keywords, study niche themes, and identify keywords that could help your website’s overall SEO.

Semrush’s database has more than 20 billion keywords, and this function gives you a detailed table with distinct subgroups organized by related search terms.

Blake Taylor of Synergy Business Brokers said of Semrush’s Keyword Magic tool, “I am a great admirer. This tool, which makes it simple to find keyword opportunities, is among the most complete keyword research tools available. In order to help you decide which keyword prospects to pursue that don’t have a lot of competition, they also give a competitive score.

Keyword Gap Analysis

To compare the keyword profiles of your top five competitors in-depth, use Keyword Gap Analysis. You may view the best prospects for each individual website, how many keywords overlap, which keywords can be found on all five websites, and more by inputting the domain and keyword ranking type.

When developing SEO strategies and campaigns, this kind of data can be useful because it gives you an understanding of the niche keywords that are currently popular. You will be able to prioritize your SEO efforts if you are aware of what your competitors are doing.

Additionally, this research will give you keywords that are exclusive to your domain, allowing you to identify keyword gaps in the campaigns of your rivals.

According to Dan Rawley of Twinkl Educational Publishing, “Semrush’s Keyword Gap feature is incredibly useful for identifying keywords that websites similar to yours rank for – especially because you can filter it to only keywords containing a certain phrase, or only those above a certain search volume.” This makes it simple for you to compile a list of the best keywords to target.

Keyword Overview

The Keyword Overview tool can be used to know more about a specific keyword’s search traffic, result number, intent, CPC, level of competition, projected value, and other factors.

Beginner digital marketers who wish to begin their keyword research journey and choose which terms they should target to increase traffic will find this tool to be extremely helpful.

“Finding keywords where your website appears on the second page of Google is the most powerful Semrush function to track and enhance your search rankings,” said Jonathan Aufray of Growth Hackers Agency. Once you’ve located these pages and keywords, head over to your page and add the relevant keywords to the H2, and H3 tags as well as the post’s body copy. Additionally, you can use internal linking with the appropriate anchor text to connect to that page from other pages on your website. Soon, your pages will appear on the first page of Google searches.

Never forget to write for your audience and readers, not search engines. As a result, be careful to include keywords in your content that are both relevant and logical. Keyword stuffing will harm your user experience and the readability of your posts, so avoid doing it.

Keyword Alert

Digital marketers used to have to manually verify which keywords had improved or declined in ranks over the previous few weeks, which takes a lot of work.

This problem was resolved by the Keyword Alert tool, which offers users a cutting-edge alert system that keeps them updated on all alterations to their ranks. Semrush notifies you via email whenever a keyword ranking in your report changes.

According to Robbie Richards, “the Alerts tool is useful for immediately noticing when keywords drop a specific number of spots or fall below the top 10.” With this knowledge, you will be able to swiftly pinpoint the problem and begin the process of regaining the ranks you so diligently worked to earn.

Keyword Tagging

To monitor the growth data of your individual tag groups, use the keyword tagging tool. This covers the share of voice, average position, traffic estimations, and visibility %. This function is excellent for assessing the visibility of your tagged keywords.

Please take note that this functionality is only available to applicants for the Guru or Business Semrush subscriptions.

According to Bruce Hogan of SoftwarePundit, “The ability to tag keywords is a valuable feature that allows us to immediately see performance changes for groupings of terms. “When we upload our keywords, we include many tags for each keyword. Then, to check the results of recent searches, each team member adds their tags into Semrush.

Domain Overview

Through a variety of overview measures, this function enables you to quickly gather knowledge about the internet presence of your website.

You’ll see a variety of items, such as backlinks, sponsored and organic search traffic, and more. You can further study the data after receiving the overview by viewing the module-specific reports.

The Domain Overview tool is excellent for identifying the advantages and disadvantages of your biggest rivals and rapidly determining which elements of your website should be optimized.

The domain overview is a great place to start when analyzing competitors. The tool incorporates link data in addition to keyword ranking data to determine how various pieces of content are being pushed.

Data can also be exported and utilized in conjunction with other Semrush modules, such as Site Audit, to reverse-engineer a competitor’s strategy and discover how their technical setup, content, and promotional activities work together to achieve their search visibility.

You may get a sense of the most popular trends in your business by keeping an eye on a variety of competitors. This will help you make sure that your brand is present online for the same themes that competitors are. On the other hand, you can monitor any competitor programs that might not be producing the best results, which can help you learn from others’ errors and increase your chances of succeeding where others have failed.

Traffic Analytics

An efficient and advanced research tool that provides an estimate of your website’s desktop and mobile traffic is the Traffic Analytics feature. This tool can be used to evaluate a new market’s potential and produce a successful media buying strategy.

You will be able to see exactly where your traffic is coming from, how users are interacting with your website, and which devices they are most frequently using thanks to this feature.

Professional marketers, researchers, and sales teams can benefit greatly from traffic analytics.

Here is what one of the marketers had to say about the traffic % metric, one of the most well-liked metrics in this feature.

Traffic% is a measure that Thermo Gears uses regularly, according to Julien Raby. To give us an estimated traffic volume for each keyword, it basically computes the estimated volume for a keyword and our current ranking. We like to look at trends to see if we’re gaining volume or not in particular keyword categories, even though exact numbers are typically off.

Link Building

For users looking for fresh link-building chances in their specialty, the Link Building function is fantastic. Additionally, a cutting-edge interface will be given to you so you can design an outreach campaign to draw in backlinks.

The feature includes four separate tools:

• Backlink Analytics
• Backlink Audit
• Link Building Tool
• Bulk Analysis

The Loop Marketing’s Ashley Sterling continues, “Our team concentrates on the link building/backlink tools offered by Semrush. This tool enables the creation of daily reports on modifications, alerts for potentially harmful links, and outreach to link prospects.

Project Dashboard

You can view a brief synopsis of all the most important data and information you generated with Semrush in the project dashboard.

You can connect your active projects, and the dashboard will create data widgets from the other features so you can see the overall performance of your project.

“The MOST effective Semrush component that I rely on every day for tracking and enhancing client search results is the Project Dashboard,” said Jordan McCreery of Ingrained Media. Semrush is PACKED with incredible tools, and the Project Dashboard makes it easy to see all the data in one place. Site Audit reveals the health of your site, Position Tracking keeps track of your keyword modifications, and Organic Traffic Insights paint a broad view of all the traffic over the course of the period.

Semrush Metrics: How to Track & Visualize Your Semrush Data in Databox

More than 50 new Semrush metrics have been added to our library of metrics. This means that Databox offers a wide variety of search ranking and website traffic visualization options.

You will be able to with this extensive array of new metrics

Increase your understanding of your Semrush data.

Better keep an eye on your website’s ranks

Discover fresh PPC keyword possibilities.

Monitor the results of your backlinking campaign.

View detailed statistics like as your domain ranking and authority score.

The best metrics that you can monitor are listed below.

• Estimated Traffic
• Top Keywords by Position
• Keywords in the Top 3
• Top Keywords by Position %
• Rankings Distribution
• Average Position by Competitor
• Average Position
• Top Keywords by Volume
• Visibility Trend

Estimated Traffic 

The percentage of traffic that was predicted to arrive at the website as a result of a specific keyword. The Position Tracking Report contains the measure. Although there are no daily totals for this indicator, you can see traffic data over time. As a result, you may recognize patterns.

Top Keywords by Position 

These are the top search terms listed in order of rank. You can use the table format to track changes in the positions of your top keywords on a daily, weekly, or monthly basis.

Keywords in the Top 3  

These are all the keywords that have been used to rank a domain in the top 3 of search results. You can also see this by the top 10, 20, and 100 keywords using the table format. In order to see patterns over time, you may also display this as a line graph.

Top Keywords by Position %

You can see the top keywords by position percentage in this line graph as well.

Rankings Distribution 

The following metrics are shown in this multi-metric Datablock if you want to examine all the top metrics in one table: Top 10, Top 100, Top 20, Top 3 keywords, estimated traffic, and relative visibility are all rankings of keywords.

Average Position by Competitor 

This is the total average of all your keyword campaign rankings broken down by rivals.

You can compare yourself to your top rivals using this table view.

Average Position 

This represents the total average of all your keyword campaign ranks.

You may observe the evolution of this with a line graph.

Top Keywords by Volume

The top keywords according to the estimated volume are listed here. Planning content marketing and PPC campaigns will benefit from this.

Visibility Trend

Based on the keywords you supplied to your position monitoring project, this is an estimate of how comparatively visible the domain, subdomain, or URL you are tracking is.

Free Semrush Dashboard Templates

There aren’t many tools that can match Semrush in terms of the range of SEO functions.

Semrush provides its users with more than 50 research and analytics tools, and while you will be able to get a tonne of information about your SEO efforts, you will need to spend a lot of time monitoring the changes.

For example, you’ll need to look into your Semrush account every week to observe which keywords are causing traffic to increase or decrease or to see which backlinks were broken.

Because of this, a lot of people select dashboards as an additional tool.

With dashboards, you can track organic traffic in real-time and connect particular indicators in a single report.

You can connect the following free dashboard templates with your Semrush account.

• Semrush Keyword Milestones Dashboard
• Semrush Site Audit Dashboard
• Semrush Keywords and Audits Dashboard
• Semrush Keyword Mission Control Dashboard
• Blog Traffic Distribution Dashboard

Semrush Keyword Milestones Dashboard

The issue it fixes: Content that does not appear in the top 10 results for important search phrases has a sharp decline in click rates. Research by Advanced Web Ranking found that 71% of all searches result in a click on a Google page one result. Even more shockingly, the first three results are clicked in 55% of queries!

Therefore, if marketers can move a popular keyword from position 11 to position 10, they will likely experience a significant increase in traffic. Additionally, when their material approaches rank 1, they should have exponentially better outcomes.

Semrush compiles all of your ranks using a relative statistic called “Visibility%.” Semrush provides you with an estimate based on your individual keywords because lower keywords are less visible on search engine result pages (SERPs). Your keyword rankings will rise, increasing your visibility percentage.

The Semrush Keyword Milestones Dashboard is used as follows:

The top 3 and top 10 keywords associated with your domain are tracked in the left column. Since visibility is determined by SEO, this enables you to monitor your overall success.

The middle column examines the particular words in which you perform well. Go to Semrush to determine which page is to blame for your high ranking if you are in the top 3 (or number 1) for a popular search.

Visibility is matched with organic traffic from Google Analytics in the final column. The “results” column appears here. You should observe an increase in organic traffic as more searchers actually click your links as your visibility percentage rises.

Questions it can answer:

• What keywords are crucial for organic traffic?
• What changes in organic traffic occur when a keyword exceeds a certain point?
• Are you getting clicks on your page titles?

Metrics tracked:

• Number of Top 3 Keywords, Daily
• Number of Top 10 Keywords, Daily
• Keywords Ordered by Ranking Movement
• Visibility % on SERP
• Organic Traffic by Sessions

Semrush Site Audit Dashboard

The issue it resolves: A Site Audit Score was developed by Semrush to compile all the various problems and warnings it discovers. There isn’t a precise score that every website should strive for, even if the scale runs from 0% to 100%. There will be more errors and warnings the more pages you have. Use the tool on your rivals to evaluate how you stack up if you need a benchmark.

You can get a baseline for all the pages that the crawler bot can find with Pages Crawled. You don’t want this number to decline unless you recently deleted pages on purpose! As a result, mistakes are increasing.

Use the Semrush audit dashboard as follows:

Use this dashboard to communicate any faults you encounter as well as how crawlable your domain is. The most serious red flags are errors, followed by notices and then warnings. The crawl depth stats can be used to check that the majority of pages are three clicks or less from the root. The easiest to crawl on are those.

Questions it can answer:

• Are you able to get rid of toxic backlinks?
• Is it simple to crawl your site map?
• Are you managing warnings, errors, and warnings as you expand?

Metrics tracked:

• Site Audit Score (%)
• Pages with Issues, Warnings, Errors, Notices
• Pages Crawled
• 1 Click, 2 Clicks, 3 Clicks, 4+ Clicks

Semrush Keywords and Audits Dashboard

The issue it resolves: All of the significant domain statistics provided by Semrush are examined by this dashboard. Both favorable statistics, such as keyword ranking, and negative statistics, such as errors that lower your domain authority and crawlability, are taken into account. Semrush’s internal metric, estimated traffic, is calculated by multiplying the number of searches for each phrase by the position’s click-through rate.

The Semrush Keywords and Audits dashboard can be used as follows:

Make certain that any effort you put into content marketing is backed up with a pristine, crawlable website. You don’t want to invest thousands of dollars and hundreds of hours in content marketing just to be restricted by a non-crawlable website.

Questions it can answer:

• How popular is your domain?
• What are your main keyword phrases?
• Are you removing mistakes, notices, and warnings?
• Does the traffic you generate via SEO grow?

Metrics tracked:

• Visibility Trend
• Estimated Traffic
• Top Keywords by Position
• Links with Errors
• Site Audit Results

Semrush Keyword Mission Control Dashboard

The issue it resolves: This dashboard provides a summary of all keyword-related statistics. It calculates the proportion of visitors to your site who initially arrived via organic means. Then, it covers every organic traffic initiative you’ve taken, including keyword research, visibility, and traffic projections.

The Semrush Keyword Mission Control dashboard is used as follows:

This provides an overall picture of how well you did at generating organic traffic. It can be used to synchronize traffic numbers with keyword metrics. Organic traffic ought to increase if you are successfully ranking highly for additional keywords. If not, you might want to look at your site audit.

Questions it can answer:

• How does organic traffic from high-ranking content work?
• How successfully are you competing for particular terms?

Metrics tracked:

• Keywords by Position, Volume, and % Change
• Ranking Distribution
• Visibility Trend
• Top Channels by Sessions

Blog Traffic Distribution Dashboard

The issue it fixes: Our research shows that 3% of blog posts are responsible for 80% of all blog traffic. Only 0.5% of postings get 50% of the traffic. You will therefore continue to rely on your top 0.5% of posts even as your organic traffic increases over several months. These posts can help you choose where to concentrate your content creation. Alternatively, you might improve the CTAs on these top posts to generate more leads or product sign-ups.

How to use the dashboard for blog traffic distribution:

Your blog entries are ranked in the left column based on organic traffic, and it also displays which posts are moving up or down the search results pages as a result of changes in traffic. The middle column makes it evident which posts drive the bulk of the blog’s traffic. 60% of the traffic in the example above is made up of 3 postings. The terms that drive all organic search traffic are tracked in the right column.

Questions it can answer:

• Which posts should be optimized historically?
• What search terms get the most traffic?
• Do you prioritize high-performing topics in your blogging strategy?

Metrics tracked:

• Top Keywords by Position
• Top Blog Posts by Sessions, Monthly
• Organic Search Traffic, Daily

Easily Monitor and Report Your SEO Data with Databox

Even for the most professional digital marketers, maintaining your SEO plan can be challenging because Google is continually improving its technology and changing its algorithm.

Despite the fact that Semrush can be quite useful in this regard, there are simply too many metrics and data to keep track of, making it difficult to keep up with changes.

This procedure can be made a lot simpler by using Databox.

You may create a single comprehensive dashboard with all the crucial data you receive from the various features by linking your Semrush account to Databox. This will make it quicker and simpler for you to monitor and report your SEO data.

Instead of having to manually verify every single item, our unique dashboard software will show you the real-time adjustments occurring in your Semrush account and allow you to track the changes in one place.

Additionally, by utilizing some of our cutting-edge visualization features, all the data you collect can be made considerably more understandable. Any reader of the report will be able to understand the material by turning the dry facts into lovely, customized charts and graphs.

Thanks for reading!!

Read more: What is SEMRush rank? – Guide for how it works?