How is the prioritization of Bitcoin Transactions done as of today?


How does the Bitcoin Network as of today priotize Transactions. Is it: A) [Bitcoin Days destroyed] * [Transaction fees / Size ] B) [Transaction fees / Size ]

What i am NOT looking for is links to old answers to the questions, where no one answering seemed to be really sure or links to 5 years old (and pretty certainly wrong) bitcoinwiki entries.

Please no speculation and guessing about this. There is already enough confusion/contradiction. I would rather have some practical viewpoints on this. Does someone run a mining rigg - how did he handle this? Did someone send 2 Transactions with same size AND Fees, but different Bitcoin days destroyed? Does someone know for sure that most Miners work with prioritization X, or has a link from bitcoin core? Etc.

Input welcome thx to the forum.


Posted 2017-12-12T10:58:30.413

Reputation: 287



The (close-to¹) highest block reward is achieved by including the transactions with the highest fee per weight. Deviating from that, miners are free to include any valid transactions at whim. They may for example choose to include their own transactions, transactions for their business partners, or transactions subsidized by out-of-band payments over other that would gain them higher revenue.

While a miner could still choose to select by coin-age-priority, this would neither be economically rational, nor supported by default by the latest versions of Bitcoin Core. Coin-age-priority was deprecated in Bitcoin Core 0.12.0.

¹ It's fathomable that a case could be constructed where selecting strictly the transactions with the highest fee rate would leave the block not completely full and selecting other transactions instead would increase the absolute revenue.


Posted 2017-12-12T10:58:30.413

Reputation: 51 063

Thank you, you have been right from the start! 1 year later and i could verify this. In a youtube Video Roger Ver ist talking about a 10K USD bet he had with Bitcoin Core. The purpose of the Video is something different (he wanted to point out how they played unfair to get a certain transaction included) but by watching the video it become very apparent through his reasoning that the miners prioritize by fee/weight and nothing else. And since he is running a 2 Ehash mining operation (with BCH though) i am pretty confident he knows this... – user54512 – 2019-06-26T15:21:50.653


A miner may choose to put whatever transactions they want into a block they find. So they can decide which ones to pick according to whatever rules they want.


Posted 2017-12-12T10:58:30.413

Reputation: 13 841

That's true, but I think the question is whether there are particular rules that are used by most miners. For example, if several large pools have publicized the rules that they use, this could effectively answer the question. – Nate Eldredge – 2017-12-12T17:09:36.103

Thats very true. I think it is likely many miners follow similar rules, but until they publicly verify that, its a guessing game. I'm wondering if there are any reasons a miner wouldn't publicly declare this, like if they have a scheme that nets them more profit that would be diminished by making the scheme public knowledge. For example: does padding your blocks with txs that have a certain minimum fee rate work better if others don't know you are doing this? Or if they just don't know the specific fee rate? etc? I think there are cases where this would be true. – chytrik – 2017-12-12T23:36:07.447