I've been asking the same question myself though I'm not trying to get paying customers. I'm offering free stuff but I can't get many takers. One customer per 1000 views is pretty much the best you can expect. You need a million views to snag 1000 customers. I would suggest that you stick to your plan and go through the free routes first. This will help you to gauge the level of interest before you bankrupt yourself paying for marketing (which never lives up to expectations).

I do have an anecdote. I have a repository on the Internet Archive. One of my items had just a few hundred views but, all of a sudden, it accumulated over 3000 views. I posted a comment on the item asking what sparked the sudden interest. Someone replied that it was a user comment on Youtube. Makes me wonder if I'm not making a huge mistake by not registering on Youtube so I can post self-promotional comments everywhere.

Obligatory shameless plug is below.

https://8chananon.github.io

Have a look through this guys 'tactics' and maybe tweak your site. https://www.kolenda.io/

Make your tool better. Clearly the users either do not understand it or do not find it valueable

Is the traffic real people or just bots? Do you know how to tell the difference?

If they are real people, how many pages are they viewing per visit? What’s average session duration? Where do they drop off?