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What Is the Bitcoin Halving and Why Does It Matter?
The Bitcoin halving is one of the most consequential scheduled events in the cryptocurrency market. Hard-coded into Bitcoin's protocol, a Bitcoin halving occurs every 210,000 blocks, roughly every four years, and cuts the block reward paid to miners exactly in half. Since Bitcoin launched in January 2009 with a 50 BTC genesis reward, four halvings have already taken place. The most recent Bitcoin halving on April 20, 2024, dropped the block subsidy from 6.25 BTC to the current 3.125 BTC per block. The next Bitcoin halving is projected for approximately April 2028 at block 1,050,000, when the reward will fall to 1.5625 BTC.
This event matters because it directly reduces the rate at which new Bitcoin enters circulation. With a hard cap of 21 million BTC, Bitcoin's entire supply schedule is fixed in advance. The halving mechanism ensures that scarcity increases predictably over time, which many economists and investors believe is a structural driver of long-term price appreciation. As of 2025, more than 93% of all Bitcoin has already been mined. The remaining supply will be released over more than a century, with the last bitcoin projected to be issued around 2140.
To explore the full schedule, visit the Supply Schedule tab in the Bitcoin halving calculator above, which shows block reward, era BTC issued, cumulative supply, and percentage of the 21 million cap for each of the first 11 halving eras. For a broader view of your crypto investment calculators and portfolio tools, explore the investing section.
Bitcoin Halving History: Prices, Blocks, and Rewards
Each Bitcoin halving has been a landmark event with distinct market conditions and outcomes. The first halving on November 28, 2012, at block 210,000 reduced the reward from 50 BTC to 25 BTC. Bitcoin was trading near $12 at the time. Within twelve months the price exceeded $1,000, a gain of over 8,000%. The second Bitcoin halving on July 9, 2016, at block 420,000 cut the reward to 12.5 BTC when the price was approximately $650. By December 2017 Bitcoin reached nearly $20,000. The third halving on May 11, 2020, at block 630,000 reduced the reward to 6.25 BTC with a price of around $8,600, followed by a bull run to roughly $69,000 in November 2021.
Historical data compiled by Investopedia's Bitcoin halving guide shows that in each cycle, the 12 to 18 months following a Bitcoin halving produced the largest price gains. Analysts attribute this to the supply shock: the daily issuance of new coins drops dramatically while demand may remain constant or increase. However, each cycle has also shown diminishing percentage returns as Bitcoin's market capitalization has grown, making extrapolation from earlier halvings an imperfect guide.
To calculate what a previous or future BTC position might be worth given different price scenarios, use our crypto profit calculator, which handles multiple buy orders, exchange fees, and ROI in a single tool.
How the Bitcoin Halving Affects Mining Profitability
For Bitcoin miners, the halving is an existential business event. When the block reward is cut in half, a miner earning 3.125 BTC per block will earn only 1.5625 BTC for the same work after the next Bitcoin halving. If the BTC price does not at least double, the gross revenue from mining falls. This squeezes margins for every operation because electricity costs, the dominant variable expense, remain constant regardless of the block reward.
The Mining Economics tab in this Bitcoin halving calculator lets you enter your miner specifications, hash rate in TH/s, power draw in watts, electricity cost per kWh, and current BTC price; to generate a side-by-side comparison of daily BTC mined, daily revenue, electricity costs, and net profit under the current 3.125 BTC reward and the post-halving 1.5625 BTC reward. The break-even BTC price metric is particularly valuable: it tells you the minimum price at which your specific setup stays profitable after the reward cut, even before any price movement occurs.
Miners who are marginally profitable at current prices should model their economics carefully. A combination of this Bitcoin halving calculator and our dedicated mining profitability calculator (which incorporates pool fees, network difficulty, and a full sensitivity analysis) will provide the most complete picture before committing to hardware purchases.
It is also important to understand how network hashrate adjusts after a halving. Bitcoin's difficulty algorithm recalibrates every 2,016 blocks. If the halving forces high-cost miners offline and total hashrate drops significantly, the difficulty decreases at the next adjustment, improving returns for miners who remain. This self-correcting mechanism has historically prevented a death spiral scenario in which falling profitability permanently damages the network.
Bitcoin's Supply Schedule and the Path to 21 Million BTC
Bitcoin's total supply is capped at 21 million coins by its source code, a limit described in detail on Bitcoin.org. Each mining era produces exactly 210,000 blocks. At genesis, every block created 50 new BTC, meaning the first era issued 10.5 million coins, exactly half of the total cap. The second era issued 5.25 million, the third 2.625 million, and so on. Because each era issues half the coins of the previous era, an infinite geometric series converges precisely at 21 million.
The Supply Schedule tab visualizes this progression across all 11 eras displayed in this Bitcoin halving calculator. By halving era 4, the current era, over 93% of all Bitcoin has already been issued. By halving 7, over 99% will be in circulation. The last fractions of a bitcoin will be issued so slowly that the practical supply issuance rate will be near zero well before 2140.
This predictable supply trajectory stands in sharp contrast to fiat currencies, where central banks can expand monetary supply in response to economic conditions. If you are evaluating Bitcoin as an inflation hedge relative to other asset classes, our crypto profit calculator and crypto gas fee estimator can help you model the full cost basis of holding and transacting on-chain.
Planning Around the Next Bitcoin Halving
For investors, the Bitcoin halving countdown is a key planning input. Historically, the 6 to 12 months before a halving have seen increased speculative interest as market participants position for the anticipated supply shock. The 12 to 18 months after have typically produced the peak of the subsequent bull market. Understanding where in the four-year cycle Bitcoin currently sits can inform decisions about dollar-cost averaging frequency, position sizing, and profit-taking thresholds.
The Halving Countdown tab calculates the exact number of blocks remaining until block 1,050,000, converts that to days and months based on the current average block time, and estimates the calendar date of the next Bitcoin halving. You can verify the current block height using any public block explorer and input it directly into the calculator for the most accurate estimate. Because Bitcoin is classified as a commodity under US law, the CFTC's digital assets resources are a useful primary source for understanding how Bitcoin and other digital assets are regulated in the United States.
Whether you are a long-term holder, an active trader, or a mining operator evaluating equipment ROI, the Bitcoin halving is a foundational event in your planning horizon. Use this Bitcoin halving calculator alongside the full suite of crypto investment calculators to model every dimension of your strategy.