My estimation on an equilibrium point of the dynamic block size proposal.
I categorized transactions by transaction types (Runes / not Runes) and sent amount (BTC) from block height 943,139 to 956,005 (April to June 2026):
| Category | Tx Count | % of all | Tx count / block | Median Tx Size (vB) | Average Tx Size (vB) | Median Sent (BTC) | Average Sent (BTC) |
|---|---|---|---|---|---|---|---|
| Runes | 32,390,725 | 58.1% | 2517 | 140 | 143.6 | 0.00022330 | 0.00098012 |
| ≤ 0.0001 BTC | 1,623,181 | 2.9% | 126 | 153 | 335.4 | 0.00000546 | 0.00002511 |
| 0.0001 – 0.001 BTC | 4,251,173 | 7.6% | 330 | 141 | 179.7 | 0.00045576 | 0.00048786 |
| 0.001 – 0.01 BTC | 7,745,101 | 13.9% | 602 | 142 | 207.2 | 0.00313992 | 0.00388373 |
| 0.01 – 0.1 BTC | 5,462,800 | 9.8% | 425 | 153 | 298.3 | 0.0248835 | 0.03361019 |
| 0.1 – 1 BTC | 2,595,252 | 4.7% | 202 | 184 | 703.3 | 0.29558826 | 0.37517733 |
| > 1 BTC | 1,692,181 | 3.0% | 132 | 206 | 794.8 | 4.37674230 | 39.21049520 |
| Total | 55,760,413 | 100.0% | 4334 | 140 | 221.7 | 0.00064009 | 1.21183610 |
Then, I applied various survival rates (*) at 40 sat / vB fee level (Jameson’s recommended fee level). (*) Higher fees price out transactions. Tiny transactions will get most affected while larger transactions will be affected less.
| Category | Current Tx count / block | Survival rate at 40 sat/vB | Tx count / block at 40 sat/vB | Average Tx Size (vB) | Current block foot print (vB) | Block footprint at 40 sat/vB (vB) |
|---|---|---|---|---|---|---|
| Runes | 2517 | 5% | 126 | 143.6 | 361,491 | 18,075 |
| ≤ 0.0001 BTC | 126 | 5% | 6 | 335.4 | 42,311 | 2,116 |
| 0.0001 – 0.001 BTC | 330 | 25% | 83 | 179.7 | 59,372 | 14,843 |
| 0.001 – 0.01 BTC | 602 | 40% | 241 | 207.2 | 124,721 | 49,888 |
| 0.01 – 0.1 BTC | 425 | 80% | 340 | 298.3 | 126,646 | 101,317 |
| 0.1 – 1 BTC | 202 | 90% | 182 | 703.3 | 141,854 | 127,669 |
| > 1 BTC | 132 | 100% | 132 | 794.8 | 104,527 | 104,527 |
| Total | 4334 | 25.6% | 1108 | 221.7 | 960,922 | 418,434 |
=> 1MB block would shrink to 418KB (based on my rough assumption). Fees per block will be 418,434 vB * 40 sat/vB = 0.167 BTC/block.
Runes The biggest lever is price elasticity of Runes transactions, but I put a very(?) low survival rate. When transaction cost gets tens of times higher, minting lottery tickets randomly will become economically unjustifiable. Furthermore, Runes movement itself could be ephemeral.
PQ Signatures If we all transition to a hash-based stateless PQ signature, transaction size would grow 61.4% on average. This will push survival rates slightly lower and the equilibrium point would be somewhere between 500KB to 600KB, which means fees per block will be 0.2 - 0.24 BTC/block .
Scaling solutions Any scaling / aggregation solution will further decrease block demand. In the post subsidy world, we cannot purely celebrate clever scaling solutions if demand does not follow well .
BTC price If BTC price gets higher, so do fees. Both users’ transaction value and their willingness to pay fees are somewhat fiat-denominated. If BTC price soars, transaction demand could be dwarfed further in the long term. Security budget (fees per block) will not grow proportionally with Bitcoin’s market cap.