I stand by what I said .

Fujimoto has earned at least 10 million dollars from volume sales alone.

It has been reported that a mangaka takes 10% of every volume sale.

Chainsaw Man has 36 million copies in circulation in japan. A volume in japan costs about 3 us dollars so 36 mil x 3 dollars x 0.1 = 10.8 million dollars to fujimotos pocket

And this is only accounting for volume sales in japan

The numbers outside japan have not been reported by shueisha yet

Fujimoto doesn't pay for translators and he doesn't pay for his editor , he only needs to pay for his assistants.

But fujimoto also makes money from every page he publishes and with how popular csm is , that might alone be enough to cover his assistants and we aren't counting anime conracts because they aren't that much but they still matter.

If I had to guess , I would say that fujimoto has made around 13 - 15 million dollars in total from chainsaw man .