The next block

The primary market for Bitcoin blockspace

What a kilobyte in the next blocks costs: the fee rate a new transaction pays to get its bytes into a block. Blockspace already used, and resold as inscriptions and tokens, is the secondary market: every listing, cheapest first, on the space.market board, and priced per kilobyte at blockspace.markets.

As of block 972,488, 15:05 UTC, 21 October 2026. From Blockspace Co.'s own node (Bitcoin Core 28.2.0). Rebuilt every 10 minutes. As JSON

What 1 kB costs

1 kB here is 1,000 virtual bytes (vB): a transaction's weight divided by 4 (BIP 141). The cost is the fee rate times 1,000 vB, in sats, as of block 972,488. The first three are the node's fee estimates (estimatesmartfee, in economical mode, the default since Bitcoin Core 28.0: release notes); the fourth is the block the node would hand a miner now.

Within 2 blocks1,011 sats / kB1.01 sat/vB × 1,000 vBestimatesmartfee 1 · as of block 972,488 Asked for the next block; the estimator's shortest target is 2 blocks.

Within 3 blocks1,011 sats / kB1.01 sat/vB × 1,000 vBestimatesmartfee 3 · as of block 972,488

Within 6 blocks1,011 sats / kB1.01 sat/vB × 1,000 vBestimatesmartfee 6 · as of block 972,488

The node's block template5,827 sats / kBthe median fee rate in the template for block 972,489: 5.83 sat/vB (lowest 0.28, 90th percentile 10.1); 3,661 transactions, 100.0 % of a blockgetblocktemplate · as of block 972,488

The estimate and the blocks disagree, and both are shown. Bitcoin Core 28.2.0's fee estimator does not go below 1 sat/vB: that is its lowest fee bucket (MIN_BUCKET_FEERATE = 1,000 sat/kvB). Recent blocks confirmed transactions below it: in the last 6 blocks, median fee rates ran from 0.14 to 1.21 sat/vB, and the lowest fee rate in any of them was 0.00 sat/vB (getblockstats reports their minimum fee rates, rounded down to whole sat/vB, as 0, 0, 0, 0, 0, 0). The estimates above (1.01 sat/vB at the lowest) sit at that floor, so they are not the lowest rate that recently confirmed. Neither number is a promise that a transaction will confirm.

The mempool now

Transactions this node has received and not yet seen in a block, as of block 972,488 (getmempoolinfo). Each node keeps its own mempool, under its own policy; the policy rows are this node's settings.

Transactions waiting	66,239
Their virtual size	28.44 MvB
Blocks' worth (virtual size ÷ 1,000,000 vB)	about 28.4
Fees they pay in all	17,434,104 sats
This node's mempool minimum fee rate (mempoolminfee)	0.00 sat/vB
This node's minimum relay fee rate (minrelaytxfee)	0.00 sat/vB
This node's incremental relay fee rate	1.00 sat/vB
Full replace-by-fee on this node	on

The last 6 blocks

Fee rates in sat/vB, each transaction's fee over its virtual size, weighted by virtual size; the coinbase is left out. Weight used is of the 4,000,000 weight-unit limit. The last column is getblockstats' own minfeerate, which it gives in whole sat/vB.

Block	Mined	Transactions	Weight used	Fees (sats)	Lowest	10th pct	Median	90th pct
972,488	14:07 UTC	2,974	99.8 %	2,222,765	0.00	0.15	1.21	3.85
972,487	13:55 UTC	6,048	99.8 %	998,147	0.14	0.14	0.14	1.51
972,486	13:52 UTC	6,801	99.8 %	716,275	0.14	0.14	0.14	2.01
972,485	13:49 UTC	4,763	99.8 %	1,652,596	0.14	0.14	1.01	3.15
972,484	13:39 UTC	3,439	99.8 %	2,212,622	0.14	0.14	1.21	3.62
972,483	13:28 UTC	6,368	99.9 %	966,879	0.11	0.14	0.14	2.28

How blockspace is bought

Through the public mempool. A transaction pays a fee: the difference between what its inputs spend and its outputs pay (Bitcoin developer guide). Nodes relay it, and miners usually choose the transactions that pay the most per unit of weight for the block they are building; getblocktemplate is how a node hands such a block to a miner. Fee estimation is "the process of estimating the feerate a transaction will need to pay to have a high probability of being confirmed within a certain number of blocks" (fee estimation).
By bumping the fee: replace-by-fee (RBF). The sender spends the same inputs again in a new version of the transaction that pays more (RBF, BIP 125). Since version 28.0, Bitcoin Core nodes accept a replacement by default whether or not the original signalled it (mempoolfullrbf=1, release notes).
By bumping the fee: child pays for parent (CPFP). The receiver (or the sender's change) spends an output of the stuck transaction in a new one with a high fee, so that a miner who wants the child must also include the parent (CPFP).
Out of band. Some payers pay a miner directly, outside the transaction, to include it: "payments made directly to a specific miner (or group of miners) in exchange for confirming one or more transactions" (out-of-band fees). Those payments are not visible in the transaction, so the figures on this page do not include them.

This page describes the market; it sells nothing, offers no service and recommends nothing.

The terms, defined once with their sources on blockspace.wiki: primary market · secondary market · fee rate · virtual byte (vB) · block template · replace-by-fee · full RBF · CPFP · out-of-band fee.