If you think about it, Google keyword planner isn't going to be doing itself any favors by reporting completely accurate information.
Google knows that a lot of people using the Google Keyword Planner tool are not looking to launch AdWords campaigns or any kind of advertising campaign on its system.
Instead, they're trying to do it for SEO purposes.
So there is a lot of incentive on their part to hide the ball.
Ahrefs works along the lines of projection.
So, basically, it would take a small data set and make predictions or projections of it.
Sometimes, it’s on point. And in other cases, it’s just completely off the mark.
That's to be expected. That's the kind of risk you run when you use projections.
Google Keyword Planner, on the other hand, uses traffic ranges—and it doesn't really need to do that.
It could give you accurate information if it wanted to.
It just wants to hide the ball because it wants to keep people guessing.
So if you are looking to build a site using these tools’ data, I would suggest using a set of many different tools.
So use Ahrefs, Semrush, and other tools, and come up with some sort of average.
The truth is tools like Ahrefs have told me in the past that a keyword has zero or low traffic, and it turned out that I get a lot more traffic from those keywords.
Remember, these are just projections.
So I would suggest that you should allow them to guide you, but at the end of the day, it all boils down to search intent.
Focus on the reason why people enter a certain keyword into Google to look for your content instead of another keyword.
Base your content on that intent, and you will do better.
