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I Just Went Full Time On My Side Project That I Grew To 2.5M Visitors

Ruurtjan Pul
Founder, nslookup.io
from Ede
started September 2019
alexa rank
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I Just Went Full Time On My Side Project That I Grew To 2.5M Visitors

Hello! Who are you and what business did you start?

Hi! I’m Ruurtjan Pul, and I run a small portfolio of web tools. My two most successful projects so far are a DNS lookup tool and an ISP checker. Combined, they have about 250k monthly unique users.

In February this year, I quit my job to work full-time on these projects. They still don’t make enough profit to make a living, but I’m giving it at least until the end of the year. NsLookup currently makes around $500 a month, and I’m looking for a partner to exclusively sell ads to.

What's your backstory and how did you come up with the idea?

Entrepreneurship has always interested me, even if I didn’t realize it at a young age. I ran a monthly single-page school tabloid with a friend at the age of 10, which we sold for — if I recall correctly — €0,01 each.

Around the same time, I tried to make a flash game aggregation site. Remember those? With only rudimentary knowledge of HTML and a bit of PHP, I never managed to launch it. But looking back now, it’s clear to me that the idea of running a website has always excited me.

Throughout my secondary education and university, I’ve also done a lot of passion projects. The vast majority never saw the light of day or didn’t gain traction, though. One of which was whoismyisp.org, which is now whatismyisp.com.

Some time in my early career, the seemingly never-ending stream of half-finished projects started to bother me. I decided that I needed to pick something and stick with it if I wanted to do this for a living. My document of project ideas was plentiful, so I sat down and evaluated them based on three criteria:

  1. Will it stay relevant for a long time?
  2. Can I make a living with it?
  3. Can I pull it off?

Read my article on picking a side project for a detailed write-up of these criteria.

Take us through the process of creating your sites.

The first prototype of NsLookup.io was a simple Bootstrap project, with a much too complicated AWS Lambda, S3, Cloudfront, and Terraform backend. It drowned in technical debt before even launching. I didn’t work on it for about a year because I couldn’t find the motivation to work through the complexity.

The initial version of nslookup’s landing page

Then I started from scratch and made a much simpler version using tech I was already used to. I took many shortcuts to launch as soon as possible and still ended up spending months before putting it live.

When I added a logo, it was just a font from dafont.com’s first page of sans serif fonts in a color I took from another brand. It’s still the same to this day. While I appreciate that design has a big influence on UX, I haven’t gotten around to hiring a freelancer yet.

The initial version of nslookup’s result page

Describe the process of launching the business.

The goal of nslookup has always been to gain traffic through search engines. So a big launch didn’t seem to make sense. Besides, SEO takes a lot of time, so I might as well start as early as possible.

And so, the launch wasn’t exciting. I put it live, and obviously, nothing happened. It took three months of working on nslookup in my spare time before I got a single visitor on most days. One year in, it was around 3000 per day. And today, almost exactly on the two-year mark, I’m at 5600 per day.


When I noticed that nslookup was finally getting traction, I started to plan for going full-time. I knew my business would be profitable as soon as I incorporated it, but not nearly profitable enough to be sustainable.

Together with my wife, we decided that we could afford to give it one year. Now, about half a year in, the profit has grown, but not nearly to the level of my previous salary. I’ve made many long-term investments, which I hope will pay off. Investments in content and quality.

Now, it’s time to start focusing on monetization. Nslookup has never had any trackers, and I hope to make money without compromising my users’ privacy. That’s why I’m actively looking for a partner to exclusively sell my ad space to.

If you know someone who can benefit from an audience of 160k developers per month, please forward them this article, so we can get in touch!

Since launch, what has worked to attract and retain customers?

Since most of my traffic comes from Google, all the classic SEO tactics apply. Make sure you give searchers what they’re looking for. Make sure you target the right keywords. And try to get other websites to link to you.

So that’s what I’ve been working on. It’s hard to attribute my growth to a single action because SEO has a compounding, delayed effect. In any case, I know that all these things must have contributed in some way.

One measurable thing is the articles I’ve written specifically for virality. The fame is always short-lived, but it can result in some good back-links and a temporary boost in traffic.

An intriguing title and to-the-point writing style make it suitable for news aggregation sites like Reddit and, in my niche, Hacker News.

Two successful examples from nslookup are DNS propagation does not exist, and I quit my job to make free web tools:



How are you doing today and what does the future look like?

I’m halfway through my first year working full-time on these sites. Going in, I set a goal of $4k revenue and $3k profit per month. So far, I managed to grow revenue to a bit under $2k.

There is still plenty of room for growth. Both in search volume, and revenue per visitor. Until now, I’ve focused on the former. I will continue to compete for search traffic, but I’m shifting my focus to improving revenue per visitor.

I’m optimistic that I can make this business sustainable. The only doubt I have is how long it will take.

Through starting the business, have you learned anything particularly helpful or advantageous?

I’ve learned that effort and results are not as strongly correlated as I thought. Some high-effort changes I’ve done did not move the needle at all, while other five-minute tweaks did. Developing a sense for finding low-effort, high-reward opportunities is much more effective than working as hard as you can.

In terms of personal development, there are two books that helped me grow. Mindset by Carol S. Dweck and Atomic Habits by James Clear. I recommend reading them in that order. Mindset shows that nearly everything about yourself can be developed or trained. Atomic Habits gives concrete advice on how to make development automatic.

What platform/tools do you use for your business?

Both nslookup and whatismyisp are pure software products. Since my background is in software engineering, I can get away with doing most of it myself. There are still some tools I use daily, though.

Advice for other entrepreneurs who want to get started or are just starting out?

Building a business takes time. More time than I thought. Not in terms of the hours you spend, but in terms of months of compounding growth. So if you have the luxury, take some time in the evenings or weekends to start something. That way, time is in your favor. You won’t have the pressure that you need to make it work before money runs out, but you’ll have the freedom to search for a growth tactic that works.

Are you looking to hire for certain positions right now?

I’m currently looking for developers and ops with DNS expertise, who love to share their knowledge. I’m paying on a per-article basis, and will help you improve your writing. Email me at [email protected] to apply.

Where can we go to learn more?

If you have any questions or comments, drop a comment below!

Ruurtjan Pul, Founder of nslookup.io
Pat Walls,  Founder of Starter Story
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