# Will the block reward continue halving beyond 1 satoshi if bitcoin precision goes beyond 8 decimal places?

If bitcoin precision is increased beyond 8 decimals, will the block reward continue halving forever instead of eventually going from 1 satoshi to 0 satoshi?

• Where'd you get the idea that having 8 decimals was temporary? Mar 12, 2015 at 5:26

The "8 decimals limit" is not that, but rather bitcoins are a human readable representation for `100,000,000 satoshi`: The software natively computes in satoshi.

What happens under the hood is that the limit of satoshi that a miner may claim by creating a block halves. Obviously, only whole satoshi can be claimed, (as currently they are indivisible), so after `block 6,930,000` when the reward limit drops from `1.164… satoshi` to `0.582… satoshi` per block, one cannot claim a whole satoshi anymore, as it would be greater than the limit.

If a new smallest unit of Bitcoin would have been introduced by then, we could continue to claim parts of a satoshi until the reward limit drops below that new unit.

In fact, we will be losing out on part of a satoshi in every block starting with `block 2,310,001` when the reward drops from `9,765,625 satoshi` to `4,882,812.5 satoshi` in approximately 2049.

There are several places where the 8 decimals property is listed as something that can change over time. This is true, but not in any meaningful way.

Of course Bitcoin can change. It's a piece of software that people run. If all those people agree to suddenly start using changed software, anything is possible.

Changing the number of decimals is not technically difficult. It would just require an extreme degree of consensus and coordination to make it happen. So unless not changing this is seen as a clear and inevitable danger to the Bitcoin ecosystem, it is very unlikely to ever happen (nor do I think it is necessary, but who knows what the future brings).

Once we decide to change the number of decimals, anything can be changed. Including, how the mining subsidy changes in the long term.

So, the answer to your question is: whatever the future Bitcoin ecosystem agrees upon.

• I'm not sure that changing the number of decimals is on par with "anything could be changed": Increasing divisibility would of course require a lot of changes to the protocol and programming, but conceptually is it a very small change, and not one that significantly changes how Bitcoin works: The total amount of money in the system wouldn't change (well, by a few satoshi that could additionally be mined), and most importantly, it could be done without redistributing any holdings. I get why it would still be hard, but isn't it magnitudes easier than e.g. changing the reward schedule?
– Murch
Mar 13, 2015 at 8:36
• That's all true, but it doesn't change the fact that whatever "everyone" agrees upon, can change. Obviously not everything is equally likely to be agreed upon :) Mar 13, 2015 at 13:47