Former Binance chief Changpeng Zhao’s four-month prison stay might have actually been a pretty lucrative career move. Indeed, from the moment he entered a California prison earlier this summer to his release last week, the Binance founder might well have made more money than most executives could hope to earn in their lifetime.

Although his wealth is mostly derived from equity in privately held companies, Forbes’ calculations of CZ’s net worth indicate that he could have made billions of dollars personally while serving his prison sentence. In fact, according to one such estimate, he may have made $25 million for every day he was in prison.

However, it’s important to note that another news agency with a more conservative methodology, Bloomberg, estimates that CZ actually lost money while in prison.

Detailed commentary for these estimates appears below.

Determining the dates of CZ’s prison term

In November 2023, CZ pled guilty to wilful violations of the Bank Secrecy Act that enabled money laundering through Binance.com. As a result, he agreed to resign as CEO, pay a $50 million fine, and never again publicly dispute the Statement of Facts from the US government’s lawsuit against Binance.

The judge subsequently recommended the Seattle area prison Seatac. However, for nearly five weeks, post-sentencing due process and legal formalities delayed CZ’s prison entry.

Ultimately, the Bureau of Prisons admitted him to Lompoc II, a minimum security prison near Santa Barbara, on June 2, 2024.

Once in the custody of the Bureau of Prisons, the probation department scheduled his release for September 29. However, due to his release date landing on a weekend, he officially exited his Long Beach halfway house two days early. He tweeted a standard crypto greeting on the day of his release.

In summary, CZ was in prison 117 days from June 2 to September 27, 2024. Because he paid his $50 million personal fine before he entered prison, his fine is not a factor in determining his net worth change from entry to exit.

Read more: New CZ lawsuit will ‘put blockchain analytics on trial,’ says lawyer

CZ’s 117-day change in net worth

Now with the exact dates known, the next challenge is to calculate CZ’s net worth change.

Although CZ has disclosed holdings of crypto assets BTC and BNB, most of his net worth is in the form of equity in Binance-affiliated companies. Sadly, because these companies are privately held and CZ has no obligation to publicly report his assets, this opacity makes it extraordinarily difficult to accurately calculate his net worth.

In truth, only CZ knows his own net worth.

Nevertheless, two news companies have attempted to estimate CZ’s personal wealth: Bloomberg and Forbes. Sadly, Forbes does not disclose its methodology.

Bloomberg, to its credit, rates its confidence at the lowest level possible (one out of five). It values CZ’s holdings of BTC, BNB, and Binance.us at $0 and also discounts the value of his Binance.com equity by 50% from the average EV-to-sales multiple of three peers: Coinbase Global Inc, Galaxy Digital Holdings Ltd, and Riot Platforms Inc.

On June 2, Bloomberg estimated CZ’s net worth at $36.5 billion. However, on September 27, it estimated it at $30.8 billion. Bloomberg analysts, therefore, believe that CZ lost money during his prison term.

Consider Forbes’ inverted estimate, however.

Forbes totally disagrees with Bloomberg

On September 27, Forbes estimated CZ’s net worth at $61 billion — nearly double Bloomberg’s estimate from the same date. This likely reflects Forbes’ non-zero estimates of CZ’s crypto assets and a more modest discount on his equity in Binance.us and Binance.com.

Unfortunately, Archive.org’s WayBack Machine did not archive Forbes’ estimate on CZ’s prison entry date of June 2. On the next-earliest available snapshot from May 7, the outlet estimated his wealth at $33 billion. On Archive.org’s next snapshot from July 12, this had rocketed to an estimated $57.8 billion.

Even assuming the higher of those two numbers for CZ’s June 2 prison entry, Forbes estimates that his net worth rose by at least $3 billion by the time he walked free. At a minimum, it is probably safe to assume that Forbes estimated CZ to have gained at least $3 billion — below $58 billion to $61 billion — during his prison term.

If true, that would mean that CZ gained $25 million per day in personal net worth for every day he served in prison.