What subsidy does this height permit?
What changes at the boundary?
Height 839,999 is in era 3 and has a scheduled subsidy of 625,000,000 satoshis, or 6.25000000 BTC. Height 840,000 begins era 4 and has 312,500,000 satoshis, or 3.12500000 BTC. Test both entries to isolate the boundary. Fees do not appear in this comparison because the subsidy formula does not include them.
Era numbering starts at 0. At height 0, the schedule calculation gives the initial 50 BTC subsidy. This reports the scheduled amount only; it does not claim that every historical issuance transaction output is spendable. Particular issuance and spendability are wider validation questions.
Why use integer satoshis?
The initial subsidy is 5,000,000,000 satoshis. Each era shifts that integer right by one bit, dropping fractions below a satoshi. At era 32 the result is 1 satoshi; at era 33 it is zero. An indefinitely halved decimal BTC display would suggest fractions that the integer rule never issues.
The implementation also handles extremely large era counts without performing an unsafe shift. This calculator preserves that zero-subsidy behaviour and rejects heights beyond the safe integer input range. It uses exact integer arithmetic before formatting BTC to eight decimal places.
In the Bitcoin family
The Bitcoin Ecosystem project describes 1Bitcoin1 (1BTC1) as “The Scarcity Anchor”: a store of value pegged 1:1 to Bitcoin (BTC), with a stated goal of eventual merger with BTC and supply wording “21 Million”.
The project describes its peg as algorithmic, without direct collateral, and its trust function as a reserve-proof layer where other chains in the project’s ecosystem can publish reserve proofs to the 1BTC1 blockchain.
The Bitcoin Ecosystem project describes Bitcoin Genesis 1 (BTC1) as “The Decentralised Utility & Security Chain (proof-of-work)”, with supply wording “26.6 Million per year”.
What cannot be inferred from a subsidy?
The scheduled amount is a maximum new issuance allowance before transaction fees are added. A valid issuance transaction may claim less. It does not show circulating supply, lost coins, demand, price or returns. Variable block arrival also prevents a height calculation from becoming an exact calendar countdown.
Where is the schedule specified?
Sources: GetBlockSubsidy; Main-network subsidy interval; Satoshi units. All selected amounts and fee rates in these tools are invented examples, not network observations.
Source: Bitcoin Ecosystem project descriptions.