Why is the total supply of Bitcoin limited to 21 million coins?

Introduction

The design of Bitcoin's total supply of 21 million coins is a clever mathematical puzzle left to the world by Satoshi Nakamoto. Behind this seemingly simple number lies profound economic principles and precise mathematical calculations. Through the block reward halving mechanism, Bitcoin has created a unique deflationary economic model that not only ensures its scarcity but also sets a new example for the era of digital assets.

Satoshi Nakamoto's Genius Design: The Mathematical Principles Behind 21 Million Coins

The limit of 21 million bitcoins is the result of careful design by Satoshi Nakamoto, and this number contains profound mathematical principles. Through clever algorithm design, Satoshi Nakamoto tightly coupled the total supply of bitcoins with factors such as block rewards and mining difficulty. Every 210,000 blocks (approximately 4 years), there is a halving of the block reward, with the initial reward being 50 bitcoins. After several halvings, it will ultimately reach the cap of 21 million. This design not only ensures the scarcity of bitcoins but also simulates the mining process of rare metals like gold, giving 比特幣 characteristics similar to digital gold.

Bitcoin Halving Mechanism: How Mining Rewards Affect Market Supply

The Bitcoin block reward halving mechanism is a key factor in controlling market supply. Each halving event has a significant impact on the calculation of Bitcoin mining profits, which in turn affects the supply and demand balance of the entire market. According to current data, the circulating supply of Bitcoin has reached 19,864,112 coins, accounting for 94.59% of the total supply. As the rewards continue to decrease, the new supply gradually diminishes, and this deflationary mechanism continually enhances the scarcity of Bitcoin.

| Halving Count | Block Reward (BTC) | New Supply (4 years) | |----------|----------------|-------------------| | Initial | 50 | 10,500,000 | | 1st Time | 25 | 5,250,000 | | 2nd time | 12.5 | 2,625,000 | | 3rd time | 6.25 | 1,312,500 |

The Last Bitcoin: The Mining Endpoint and Value Prediction for 2140

According to the current mining speed and reward mechanism, it is expected that the last mining time of Bitcoin will be around 2140. As the total supply of Bitcoin approaches its limit, the market's expectation of the value of the last Bitcoin is also continuously rising. As of May 13, 2025, the price of Bitcoin has reached $102,882.02, and the total market capitalization has surpassed $2 trillion, reaching $2,043,659,878,565.04. This astonishing growth trend reflects the market's recognition of Bitcoin's scarcity.

Bitcoin Scarcity: The Deflationary Economics of Digital Gold

The scarcity of Bitcoin is its core characteristic as digital gold. The fixed total supply cap and halving mechanism together constitute Bitcoin's deflationary mechanism, which stands in stark contrast to the inflationary nature of traditional fiat currencies. The investment strategy based on Bitcoin's scarcity has become the choice for many investors, especially against the backdrop of increasing uncertainty in the global economy.

According to market data, the scarcity of Bitcoin has been reflected in its price performance. The price increases over the past 30 days, 60 days, and 90 days are 22.04%, 24.87%, and 6.95% respectively, showing strong upward momentum. This continued value growth further strengthens Bitcoin's position as a hedge against inflation and a means of value storage.

The scarcity of Bitcoin is reflected not only in its total supply but also in its distribution and usage. Currently, Bitcoin holds a market share of up to 61.94% in the global cryptocurrency market, which clearly demonstrates its dominant position in the field of digital assets. With the continuous entry of institutional investors and the approval of Bitcoin ETFs, the demand for Bitcoin is expected to further increase, thus driving its value to continue rising.

Conclusion

The total supply limit of 21 million Bitcoins designed by Satoshi Nakamoto ingeniously creates digital scarcity through the halving mechanism. The current circulation has reached 19.86 million, accounting for 94.59%, while its dominance in the cryptocurrency market is as high as 61.94%. As the block rewards continue to halve, Bitcoin demonstrates a strong growth momentum, with a 22.04% increase over the past 30 days, further solidifying its position as digital gold.

Risk Warning: The cryptocurrency market is highly volatile, and changes in regulatory policies may lead to significant fluctuations in Bitcoin prices. Investors should carefully assess the risks.