Productize Your Knowledge to Earn Passive Income

5 min read

In college I earned a bachelor’s degree in statistics and a master’s degree in applied statistics.

I chose statistics as a major because I had always been good with numbers and I knew that it was a field in which I could earn a lucrative salary. This seemed to be a win-win: I could earn good money and enjoy my work simultaneously.

Of course, it wasn’t until I graduated and actually spent some time in a 9-5 work environment that I realized I would likely never enjoy a corporate job, even if I enjoyed the type of work I did.

But even though I didn’t enjoy my day job as a data scientist, I found out that my knowledge in statistics could be lucrative in a different setting: tutoring.

Statistics Tutoring as a Side Hustle

In my senior year of undergrad, I noticed a fascinating trend whenever I told other students that I was majoring in statistics. Without fail, they would almost always reply with some version of the following response:

“I had to take an introductory stats course during my freshman year as a requirement for my major and I hated it.”

In many cases, they’d go on to share that they would have been more than willing to pay someone to tutor them, but that it was so difficult to find a stats tutor.

This lead to my light bulb moment: There was a high demand for people who could tutor in introductory stats, yet very few people who had the knowledge to do so.

Basic supply and demand told me that I could charge a high hourly rate for my time as a statistics tutor, so that’s exactly what I did. I posted ads on Craigslist and found several people within my first week that were willing to pay $30 per hour for my tutoring services.

In the months that followed, I met with people at libraries, coffee shops, and Barnes & Noble cafes and tutored them all in introductory statistics. It didn’t take long for me to realize that I could increase my hourly rate to $45-50 and most people would still be happy to pay.

Trading Time for Money Has an Upper Income Limit

Statistics tutoring was a great side hustle for me. I could earn good money and I actually enjoyed helping people learn. There was only one drawback: I was trading time for money, which created a natural upper limit on how much income I could earn.

For example, I often only had two hours of free time each weekday during my senior year since I had a part-time job and classes to attend. So, if I charged $50 per hour then the most I could earn through the week was 10 hours * $50/hour = $500.

Of course, I could increase my hourly rate to $60 or even higher, but fewer people would be willing to pay this price and my income would once again hit a natural ceiling.

This brings up an important point: Whenever you trade time for money, there is an inherent upper limit on how much you can earn. This applies to freelancing, consulting, day jobs, and any other scenario in which you’re trading your time for income. There is only so much time in the day.

Fortunately, there exists another way to earn income that doesn’t require you to trade your time for money: Productize your knowledge.

Productize Your Knowledge

To productize your knowledge means to create some type of product that you can sell that encapsulates your knowledge on a particular subject.

For example, I have knowledge in statistics. When I was tutoring people in statistics, I was providing a service. This meant that they gave me money in exchange for my knowledge.

However, I could instead create a product such as an ebook, a course, or paid tutorials on statistics that I could sell to people. This meant that I didn’t need to exchange any of my time to earn money. People could simply buy my products and use those products to learn about statistics on their own time without my help.

So, that’s exactly what I did. I built Statology, a site that now has hundreds of statistics tutorials people can read through on their own time. The site is monetized with display advertisements, which means I earn a little bit of ad revenue each time someone visits the site.

The beauty of earning money this way is that I don’t have to be physically present to earn money off of my statistics knowledge. I can create a tutorial on a certain topic one time, publish it, then walk away. Then, people out there on the internet can search for the topic I wrote, find the article on Statology, read through it, and in return I receive ad revenue.

Now, instead of getting paid to help one person face to face, I can help hundreds of people each day and receive passive income in return.

I still tutor people in statistics one-on-one because it’s lucrative and I enjoy doing it, but because I have a stats website my income is no longer capped by how much time I have available to tutor people. Even when I’m not actively tutoring, my website is growing and earning money for me each day.

By productizing my knowledge, I have removed the upper limit on how much I can earn.

Other Examples of Products I’ve Created

Statology is just one example of a piece of my own knowledge I’ve productized. In addition, I’ve also productized the following things on this site:

The Excel Genuis Toolkit – This is a collection of 17 Excel worksheets that show how I made the most popular visuals on this blog. Since people emailed me so often asking for the worksheets I used to create some of the visualizations in my posts, I decided to create a massive collection of worksheets that I could simply sell to people. 

The Data Scientist Resume Pack – This is a collection of the exact three resumes I used to land various data science jobs. Instead of explaining how to create a resume that will attract data science jobs, I made this product so that people could purchase it and simply see examples of resumes that have landed real jobs.

Elements of Freedom – This is an ebook that encapsulates all of the big ideas that I’ve written about over the course of nearly three years on this blog. I decided to make this as a way to help new readers get up to speed on all of the topics I write about without needing to dig through the hundreds of articles in the archives.

How to Productize Your Knowledge

There are many ways that you can productize your own knowledge including writing an ebook, creating a course on Teachable, selling your own compilation of templates, or through writing helpful articles on a website and monetizing them with display ads.

The process for doing this is simple:

1. Find a topic that you have unique, rare knowledge in.

2. Create a product based on this knowledge that you can sell to people.

If you feel stuck, check out this page that lists out 23 examples of “niche” sites in which people are earning income from products based on niche, rare knowledge they possess on various topics.

A few of my favorite examples from that page include:

  • One guy who is an orchestra percussionist earns money by selling courses to aspiring musicians that help them prepare for interviews and auditions.
  • One woman who lives in a camper sells books and courses on tiny living and on how to live optimally in trailers and campers.
  • One guy who is a magician sells courses and paid tutorials that explain how to do various magic tricks for beginners.
  • One woman who is a painter sells courses on how to paint better and also runs a YouTube channel that is monetized with ads.

In each of these cases, these people possess a certain knowledge in a certain field. Instead of renting out their time to provide services, they have decided to create products based around this knowledge which they can sell from their website at all hours of the day to earn passive income.

“I Don’t Like Selling”

The biggest push-back I receive from people when I tell them that they should productize their  knowledge is that they “don’t like selling.” 

Personally, I was scared to sell products too when I first started, but one realization has helped me get past this fear: If someone is interested in using my product to help them in some way, they’ll buy it. And for everyone else who isn’t interested, they’ll simply move on with their life. No harm done.

For example, I only sell a few of the Data Scientist Resume Packs each month because it targets a super niche, specific group of people who are attempting to get into data science. For these people, the resume templates are extremely valuable and they’re happy to pay $15 to acquire them. For everyone else who isn’t interested in data science, they’ll simply brush over that product. No big deal.

Get Started

What specific knowledge do you possess? 

Do you know a lot about statistics, organic chemistry, or some other tricky subject?

Do you know a lot about travel hacking with credit cards?

Do you know a lot about a certain programming language or software?

No matter what knowledge you possess, there is almost always a way to monetize that knowledge by creating and selling a product.


Zach is the author behind Four Pillar Freedom, a blog that teaches you how to build wealth and gain freedom in life.

Zach's favorite free financial tool he's been using since 2015 to manage his net worth is Personal Capital. Each month he uses their free Investment Checkup tool and Retirement Planner to track his investments and ensure that he's on the fast track to financial freedom.

His favorite investment platform is M1 Finance, a site that allows him to build a custom portfolio of stocks for free, has no trading or maintenance fees, and even allows him to set up automated target-allocated investments.

His favorite way to save money each month on his recurring bills is by using Trim, a free financial app that negotiates lower cable, internet, and phone bills with any provider on your behalf.

His favorite micro-investing app is Acorns, a free financial app that takes just 5 minutes to set up and allows you to invest your spare change in a diversified portfolio.

His favorite place to find new personal finance articles to read is Collecting Wisdom, a site that collects the best personal finance articles floating around the web on a daily basis.


Full Disclosure: Nothing on this site should ever be considered to be advice, research or an invitation to buy or sell any securities, please see my Terms & Conditions page for a full disclaimer.