4,000 visitors, 120 signups, 0 paid conversations

Scale the number of touch points you have with customers based on their interaction with the tool.

Made an account but no API? Send a custom email

Made an API but 0 requests? Send a custom email

Made an API, and 100 requests but stopped using it? Send a custom email

You're in the learning stage right now. You have a product that works (based on there being competitors) but you need to figure out your customers' needs still. What's holding them back?

Fixed your bottom line first, then throw in more traffic at the top.

You mentioned sending 30 emails to users. That's only 25%. Email all 120 of them. No response? Email again. Still no response? Email again.
People sign up because they have a problem to fix. You're there to fix that problem for them. So go out and do that.

I think your project is awesome and the landing page is rock solid. It makes me want to register just by looking at it even though I have 0 use-case for your service. So probably just better sales/features to fix it.

PS: I am sending this to my ex-trivago boss who loves spreadsheets but he is also a dev.

"I have no idea why nobody has converted yet"

ASK THEM

I think these things take time to convert, people need to be aware that it exists and then formulate a plan to use it, then to prioritize it for their situation, etc.

Keep going and remember that people need trust that the service will exist for the long term.

Send them more frequent emails and solicit feedback. Ask what they want to see or what could be done better.

My hunch is that people are forgetting about your product. I would try 2 things:

1. integrating a weekly or even daily status email. Maybe you could list the usage during that week or day.

2. right after the user signs up, show an nice modal with something fun, a gif or a fancy thumbs up icon and say thanks for signing up.
   House flippers often use something similar. Paint a small toilet blue. Why? It creates a hook. Even if the house does not tick everything off the buyers checklist, most buyers will consider the house in their comparison, just because that house is harder to forget. The first time a user logs in, make sure they remember you.

Another thing you might consider is your emails. It’s weird that you’re getting so little feedback. I would advise you to keep it short and just ask if they are free for a quick call. If they say yes, you’re in and you’ll know what to do. If they say no, then ask if you can mail them the questions.
People find it easier saying yes/no than answering your questions.
Also, make sure you tell them how important they are to you. Thank them and tell them that their feedback is what makes the product better ultimately.

Hope this helps!

Who are you building this for? Who is your ideal customer?

I think you can at least double the conversion rate of visitors to trial accounts.

That's really interesting, how did you market your app to get those 4k page visits? Could it be something about the audience that's coming into the site?

Have you considered making it for landing pages, instead of just providing APIs?

Is there no ways to convert the handful of users that make 10-350 API requests into paying customers. Seems there is value in the product for them