What is the best SEMRush alternative?

SEMrush is a pretty decent tool, to be honest, especially for competition research.

I do however think there's a couple of tools you could explore as a SEMrush alternative

1. Ahrefs
2. Google's keyword planner
3. Sistrix
4. SearchMetrix
5. SEOchat Tools (early days - but free)
   
   
   

To be honest, I use a combination of tools, personally, if I had to choose one though (forgetting about the cost) I'd choose Ahrefs.

SEMrush is a pretty decent tool, to be honest, especially for competition research.

I do however think there's a couple of tools you could explore as a SEMrush alternative

1. Ahrefs
2. Google's keyword planner
3. Sistrix
4. SearchMetrix
5. SEOchat Tools (early days - but free)
   
   
   

To be honest, I use a combination of tools, personally, if I had to choose one though (forgetting about the cost) I'd choose Ahrefs.

Moz is also good - I use SEM Rush and I love it.

What is the reason you are thinking about something else?

Is there a budget you are working on? 

No budget: google related search terms, keyword surfer

Low budget: Keysearch

Mid budget: KWfinder

High budget: Ahrefs

SEMRush is the best tool for competition research. If you want to get away with it, alternatives are-

-Serpstat

-Moz

-SEO Powesuite

-Ahrefs

Serpstat is another in-depth research tool that I found in 2019. In regards to helping people identify keywords that were winning, They've done some work.