Well, it’s really only a contest between two of them – Ahrefs vs. SEMrush. Moz hasn’t been useful or had much other than Moz Local to justify their pricing structure for years, and the data you get there isn’t up to par with any other similarly-priced tool. Majestic’s main benefit is backlinks & from what I’ve heard, all other offerings from them are meh.

Ahrefs & SEMrush are the standard now in SEO – most people have both. If I had to choose, it’d be SEMrush hands down. Ahrefs has had lots of issues with their keyword data for which they have said they’ll fix, but there are still queries which haven’t been updated since December 2019. Their backlink index is great, but you can now get that for your own site for free via Ahrefs Webmaster Tools (even though they have a “recommended” option of connecting your GSC data); they say they’ll possibly, “blend” the data with their own but to what degree they haven’t said. Why would you blend data from Google with inaccurate data?

SEMrush has come through with so many different tools that I didn’t even know I needed or wanted but have helped in a ton of different ways. SEO Writing Assistant & Position Tracking from SEMrush are two tools I constantly recommend to others because of their utility and value for what you’re paying for. SEMrush also offers a free account to compete with AWT & I’d still recommend that over AWT. There are trials for most of the tools; you should check them out to see what will work best for you!