About block 939,456
Bitcoin block 939,456 was mined by Foundry USA on March 5, 2026 at 5:28 PM UTC, 3 min 33 s after block 939,455. That is faster than the 10-minute average the network aims for: blocks come in bursts because finding one is pure chance.
It confirmed 1,890 transactions in 2.72 MB (99.8% of the 4 million weight-unit limit). The median transaction paid 0.00 sat/vB, and all fees added up to 0.0114 BTC. With the 3.125 BTC subsidy of halving era 5, Foundry USA earned 3.1364 BTC for this block.
Block 939,456 is number 1 of 2,016 in difficulty epoch 466; 2,015 blocks remain until the next difficulty adjustment at block 941,471. The next halving is at block 1,050,000, 110,544 blocks after this one.
Its hash starts with 20 zeros: that is the proof of work, a number below the target that the whole network’s hashrate had to search for. Foundry USA found 250 blocks in the week before. Today the block has 36,525 confirmations, so it is settled beyond any practical doubt.
Why block 939,456 is notable
Block 939,456 opens difficulty epoch 466. Every 2,016 blocks, each node recalculates the mining difficulty from how long the previous epoch took: if those blocks arrived in less than two weeks, difficulty goes up; if they took longer, it goes down, never by more than a factor of four. The new value, 145,042,165,424,853, took effect with this block, found by Foundry USA on March 5, 2026 at 5:28 PM UTC, and applies until block 941,471; the following adjustment is at block 941,472.
Nobody schedules a retarget. It happens when the chain reaches the height, so the adjustment at block 939,456 came the moment Foundry USA found it, not on a fixed date. The rule keeps the average close to one block every ten minutes however much hashrate joins or leaves the network.
Of the 3.13644984 BTC that Foundry USA collected for this block, 3.125 BTC was new subsidy and 0.01144984 BTC came from fees, 0.4% of the total; leaving out the coinbase, its 1,889 transactions paid about 606 sats each on average.
Current difficulty epoch and next adjustment →
What’s inside a Bitcoin block
Every block, 939,456 included, is made of the same parts:
- Header
- Eighty bytes that miners hash over and over: the version, the hash of the previous block, the Merkle root that summarises every transaction, a timestamp, the difficulty target in compact form and a nonce. A block is valid when the hash of its header falls below the target.
- Coinbase transaction
- The first transaction, written by the miner. It spends no inputs: it creates the subsidy and collects the fees, and since BIP 34 it must also record the block height.
- Transactions
- Everything else in the block: payments taken from the mempool, usually picked by fee rate because space is capped at 4 million weight units. Block 939,456 holds 1,890, counting the coinbase.
- Fees
- The difference between what each transaction spends and what it creates. The miner claims them in the coinbase; they are the part of the reward set by demand rather than by the protocol.
- Subsidy
- New bitcoin created by the block, fixed by the halving schedule: 50 BTC at the start, halved every 210,000 blocks. At height 939,456 it is 3.125 BTC.