Batching: how Bitcoin speeded up

If Bitcoin transaction costs and fees are decreasing in recent weeks, is because something happened in the blockchain operations. What for months has clogged the exchanges and made to cool all the coffee purchased in Bitcoin, now has an answer: batching.


Batching is what the Bitcoin network, a strange creature ruled by worldwide developers no longer identifiable, has been optimizing time. For those who are not computer scientists, we will explain this by paraphrasing a David A. Harding’s 2017 post on Medium.

Imagine that Alice wants to buy a pizza that costs 10 Bitcoins. The operation of the blockchain works in this way: in paying it Alice puts on the plate 20 BTC, and orders the system two outputs: 10 BTC will go to the pizza maker and 10 will remain to her.

Then, concluded this transaction, Alice will remember that she must also pay the pizza maker for his work (fees). Then again she will open a transaction to tip 1.5 BTC to pizza maker. Again in doing so she will order the system to give 10 BTC to the pizza maker and to see herself back 8.5 BTC.

  • Result: 2 similar operations (payment + reward for those who operated the transaction), total 456 bytes.

How can Alice speed up the transaction? Doing the two operations (paying pizza and then tipping) in one transaction. Alice orders the system the output to give the pizza maker 20 BTC and to get back only 8.5 BTC, directly including both the price of pizza and the cost of the pizza chef’s service.

  • Result: 1 single operation (Alice pays both pizza and fee), total 260 bytes

With this system, the developers have reduced by half the heaviness and therefore the speed of each transaction, while safeguarding a correct registration on the blockchain as well as the profitability for the nodes of the system.

A faster and more efficient Bitcoin has been gaining ground in the world of cryptocurrencies since a few weeks. Waiting to see if this optimization will make it more suitable for the general public.