Name:SEMrush (Free)
URL:https://www.semrush.com/
Description:All in one marketing toolkit for digital marketing professionals 
Utility:This free tool provides the following details – 

• Source of the majority of traffic 
• Whether there are paid search or advertisements on search engines 
• Websites that posses link to the site
• What led people to the site
• Number of monthly visitors
• Main online competitors to the website