How Many Substack Millionaires Are There? (The Math Behind the Newsletter Economy) | Cal Newport

When economist and columnist Paul Krugman announced he was leaving The New York Times, the media world took notice. Reports suggested the paper wanted to restrict his newsletter output, and Krugman, feeling pushed out, decamped to Substack. At the time, this seemed like another grim milestone in the slow-motion dismantling of traditional media—a respected expert leaving a prestigious institution for the digital wild west.

However, insiders suggest a different reality. Krugman isn't just surviving on his own; he is thriving. His subscriber count rivals the Sunday print circulation of major papers, and his earnings have likely leaped into the seven-figure range. This raises a provocative question: Is the pessimistic narrative about the death of journalism wrong? Could paid email newsletters actually be the foundation for a new, sustainable type of professional media, or is Krugman merely an outlier cashing in on a vanishing era of expertise?

Key Takeaways

• Top-tier potential is massive: Based on subscriber math, top writers like Paul Krugman are likely earning between $1.2 million and $4 million annually.
• The "middle class" is growing: Beyond the famous outliers, roughly 500 to 1,000 writers are currently earning a substantial full-time living ($150k+) via newsletters.
• It replaces the present, not the peak: The newsletter economy can likely scale to rival the current, diminished state of the newspaper industry, but it will not match the revenue or employment levels of print media at its 20th-century peak.
• The "Enshittification" risk: The biggest threat to this ecosystem is Substack shifting from a neutral utility to an attention-capture platform similar to social media.
• Digital Minimalism strategy: Successfully leaving social media requires aggressively filling the "void" with meaningful activity rather than relying on willpower alone.

The Economics of a Substack Millionaire

To understand the newsletter economy, we must look at the underlying math. Using Paul Krugman as a case study provides a window into the upper echelon of this market. His Substack currently boasts over 505,000 subscribers. While the platform does not publicly release the exact breakdown of paid versus free readers, we can apply standard industry conversion rates to estimate revenue.

Crunching the Numbers

Substack generally suggests that a healthy newsletter converts 5% to 10% of its total list into paid subscribers, with 3% being a conservative floor. With a subscription price of $7 per month, the potential revenue scenarios are striking:

• Conservative (3% conversion): Roughly 15,000 paid subscribers generating nearly $1.26 million per year.
• Moderate (5% conversion): Roughly 25,000 paid subscribers generating over $2 million per year.
• Optimistic (10% conversion): Roughly 50,000 paid subscribers generating over $4 million per year.

Even in the most pessimistic scenario, Krugman is generating revenue that likely far exceeds his former salary at the Times. However, this level of success requires a specific workflow. Analyzing the habits of comparable writers like Nate Silver reveals that maintaining a top-tier newsletter is effectively a full-time job, requiring 40 to 50 hours of work per week. Success demands high frequency (often 3+ posts a week) and content that is both timely and differentiated from the general news cycle.

Sizing the Market: Is There a Middle Class?

While Krugman represents the 1%, a sustainable media economy requires a middle class. How many people are actually making a living wage writing online? Research into the Substack leaderboards across major categories—Politics, Culture, Technology, Business, and Finance—offers some clarity.

At the very top, the air is thin. There appear to be only about 34 to 50 newsletters across all categories with subscriber counts in the Krugman range (500,000+). However, when we look at the 20th ranked newsletter in these major categories, the numbers remain robust.

In the "Politics" category, the 20th ranked newsletter has roughly 200,000 subscribers, implying a potential income of over $800,000 annually. Even in "Technology," the 20th spot holds nearly 100,000 subscribers, translating to roughly $400,000 a year. When extrapolating across all categories, we can estimate that there are currently 500 to 1,000 writers earning a high-end living ($150,000+) solely from their newsletters.

Newsletters vs. The Ghost of Print Media

Can this distributed network of writers actually replace the institution of the American newspaper? To answer this, we must compare the optimistic future of Substack against the historical data of the print industry.

At its peak around 1990, the US newspaper industry boasted a circulation of 60 million and employed roughly 56,000 reporters and editors. By 2005, advertising revenue peaked at $50 billion. Today, those numbers have collapsed: circulation is around 20 million, and revenue has plummeted to roughly $11 billion.

The Replacement Theory

Hamish McKenzie, co-founder of Substack, has stated a goal of reaching 50 million paid subscriptions. If the platform achieves this 10x growth from its current state, the comparison looks interesting:

• Circulation: 50 million subscribers would rival the newspaper industry at its absolute peak.
• Revenue: At that scale, revenue would sit around $4.5 billion. This is a fraction of the newspaper industry's 2005 peak ($50 billion) but is comparable to where the industry is trending today.
• Employment: This growth might support 5,000 full-time writers. This is significantly fewer than the 56,000 journalists of the 1990s, but it represents a robust, decentralized workforce.
• Conclusion: The newsletter economy likely cannot replace the financial might of the old mass-media model, but it can offer a viable alternative to the diminished state of modern legacy media.

Furthermore, the shift to individual writers may solve a trust crisis. In an era where trust in institutions has plummeted, readers are increasingly comfortable placing their trust in specific individuals. We understand human bias; we can filter Paul Krugman’s opinions through our knowledge of his worldview more easily than we can filter the "view from nowhere" presented by a corporate masthead.

The Risk of "Enshittification"

The most significant threat to this optimistic future is the platform itself. There is a fundamental tension between Substack as a utility (like WordPress) and Substack as a social network (like TikTok). Writer John Gruber has criticized the tendency to treat Substack as a destination rather than a tool.

"We constrain our imaginations when we subordinate our creations to names owned by fascist tycoons. Imagine the author of a book telling people to 'Read my Amazon'... There is no such thing as my Substack, there is only your writing in a forever fight against a world of pure enshittification."

The danger lies in Substack pursuing a "unicorn" valuation ($100 billion+). To achieve that, they may be tempted to turn the platform into an algorithmic feed—a "stream of distraction"—rather than a direct connection between writer and reader. If Substack prioritizes engagement metrics over the sanctity of the inbox, the ecosystem could degrade into the same low-quality noise that plagues social media. For the newsletter economy to truly save journalism, it requires open-source or indie alternatives that allow writers to own their audience without relying on a centralized tech giant's algorithm.

A Practice for the Distracted World: Handling the Void

Moving from the macro economy to personal practice, many of us are entering the new year with a resolution to use our phones less. A recent clip from my conversation with Andrew Huberman regarding this topic went viral, specifically because it addressed the psychology of addiction rather than just the mechanics.

The core insight is that excessive phone use is often an attempt to "paper over the void." We use screens to numb ourselves to boredom, anxiety, or a lack of fulfillment. Therefore, the most successful strategy for digital minimalism is not "white-knuckling" through willpower. It is aggressive replacement.

To succeed in putting the phone down, you must:

1. Admit that the phone is solving a problem (avoiding the void).
2. Aggressively pursue high-quality alternatives: new hobbies, real-world social connections, and difficult projects.
3. Fill the void with meaningful action so that the need for the digital pacifier evaporates.

When you activate your human brain with genuine challenges and connections, the shallow appeal of the algorithm naturally fades. The fight for depth isn't just about removing distraction; it is about building a life so good that distraction becomes irrelevant.

Conclusion

Whether we are analyzing the macro-economics of the media industry or the micro-habits of our daily lives, the theme remains the same: the battle between depth and distraction. Paul Krugman’s success proves that there is a massive market for deep, expert thinking. The newsletter economy offers a hopeful, albeit smaller, lifeboat for journalism in a digital age. However, realized potential—both for the economy and for our own peace of mind—requires intention. We must support platforms that prioritize direct connection over algorithmic feeds, and we must structure our lives to prioritize meaningful action over passive consumption.