Free SEO tools list - On-Page, Off-Page and Backlinks checker

What are the best SEO tools available for free ? I would like to do On-Page analysis, Off-Page analysis. I also would like to check as many backlinks as possible.

Free SEO tools often have some limitations, so you can do only a limited number of analysis per day, you can see a limited number of results or you can use only a limited features. But many of them are really useful within a free plan.

On-Page and Off-Page free SEO tools:

• Seobility.net - performs a SEO analysis. It is focused on 6 main categories: Meta information, Page quality, Page structure, Link structure, Server and External factors.
• Seositecheckup.com - performs a detailed SEO analysis and shows a SEO score. It provides you the suggestions for improvements.
• Neilpatel.com - performs an analysis of 150 website pages during a few minutes. It allows to do 3 searches per day. Overall website audit can be performed once during a certain period of time.
• Seoptimer.com - performs a detailed SEO analysis. It is focused on 5 main categories: On-Page SEO, Links, Usability, Performance and Social.
• Semrush.com - provides a solid range of information within a free plan. You can check backlinks, keywords, SERP positions. It is needed to create an account. The number of seraches is limited.
• Pagespeed.web.dev - measures web page loading speed on mobile and desktop devices. It is focused on Largest Contentful Paint, First Input Delay, Cumulative Layout Shift, First Contentful Paint, Interaction to Next Paint, Time to First Byte, Speed Index and Time to Interactive.
• Search.google.com/test/mobile-friendly - tool that checks if website is mobile friendly.

Free Backlink checkers:

• Monitorbacklinks.com - provides a limited (but quite long) list of backlinks with information like trust flow, citation flow, number of links, status. To see more links, you have to click on "Load more" button. You can export the list of links into CSV.
• Ahrefs.com - provides a list od top 100 backlinks, top 5 anchors and top 5 pages. You can detailed information about Domain rating, URL rating and Reffering domains.
• Moz.com - provides a limited list of backlinks with Domain authority and Page authority. It allows to do 10 searches per a certain period. You need to create a free account.

Seobility.net has also a quite good free backlink checker. You can get a long list of backlinks + link rating for free. There are 3 backlink analysis available for free per day.