the wide discrepancy in search volume between Ahrefs and other tools

I get that various tools use different methods to estimate search volume and that different results should be expected, but the numbers I'm getting with some keywords aren't even in the same ballpark. Example:

Moz: 51-100 monthly searches
Keyword planner: 100- 1 K
Semrush: 380
Ahrefs: 7.000 ????

I'm planning to start a keyword service using Ahrefs, but I'm starting to have second thoughts about using it since clients would get suspicious and question the accuracy of the data. What do you guys think?

What I suggest is use a few different tools, as no tool is perfect, so I use 2,3 tools to gauge traffic; at least you can get a relative comparison between keywords. Knowing the true real user search volume is probably impossible unless you work at google.

The only tool you can rely on for keyword ms number is google keyword planner.

Unavailable said:

The only tool you can rely on for keyword ms number is google keyword planner.

Click to expand...

Can you? "The average number of times people have searched for a keyword and its close variants"
How do you go around these "buckets"?