Should I make my free deliverability tool paid?

I’m genuinely confused and would love some advice.

I built Inbox Placement Test as a free tool: real mailboxes, 24-hour monitoring, SPF/DKIM/DMARC checks, no signup, API/MCP.

But I keep seeing paid deliverability products get much more attention and hundreds of Product Hunt upvotes.

For example, Hello Inbox has paid plans and got a lot more traction than my free tool.

So I’m wondering:

Does “free” actually make the product look less valuable or less trustworthy?

Would you:

• keep it completely free,

• add a paid tier,

• or make the core free and charge for integrations / higher limits / team features?

I’m not trying to maximize revenue right now. I’m trying to understand how people perceive value in this category.