Grin transaction fees

This infographic seems to say that transaction fees are 4 milligrin per output with a discount of 1 milligrin per input, but at a minimum 1 milligrin of fee.

Is possible to pay less fee?
Is it possible to pay more fee?

If it is not possible to pay more fee, what happens when blocks become full, and what about miners mining empty blocks if they deem fees to be negligble?


It’s not configurable now but I guess it’s going to be once the block size starts being an issue.

Which could be years from now, or even perhaps never.

Are you saying that there will need to be a hardfork, or are you just saying that the current wallet doesn’t support it?

It’s just the wallet that does not support it.

So, the question stands regarding minimum fee. Does it exist, or is tx_weight/1000 just how it’s implemented in the wallet?

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I have a noob question: I see BTC fee now nearly cost $40, I just imagine, what a maximum fee for standard transaction if the network is busy? or people can bid the priority to any value they want?

Yeah… thx to Ordinals :clown_face:

Miners have to be successful as Saylor said:

For Grin there is a formula:

(num_inputs + num_outputs * 21 + num_kernels * 3) * fee_base

where is fee_base is 0.0005

accept_fee_base and max_pool_size are also options on node to handle “mempool”:

Will be interesting to test how it will work on Grin network load with high payments amount for sure, I guess pools can tweak these values for better bandwidth.

Also it’s good we have no such thing as ordinals and other bloatware to spam the chain :slight_smile:


This future became closer than we thought.


Hello, on Grin++ the tx fee is automatically set at 0.0125 Grin. Is it posible to set a lower tx fee ? :thinking:

You cannot. The minimum fees are there to protect the chain and mempool from spam attacks. They are calculated giving weights to inputs, outputs and kernels based on how much memory these parts of the transaction will use on-chain. So basically you pay linearly for the blockchain space you use.

See this link for how fees are calculated:

Not sure how Grin++came to 0.00125, especially the 0.00005 part has me puzzled. Probably @tromp can explain it

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The current fee rules are described in grin-rfcs/text/ at master · mimblewimble/grin-rfcs · GitHub

Standard fees are multiples of accept_fee_base which equals half a milligrin, so a fee of 0.00125 is not standard. I have no idea how grin++ computes fees, but apparently it’s not following the standard formula.


Hey Tromp
Is milligrin the equivalent to a btc satoshi?

I was wondering what its called

No; nanogrin is the smallest unit.

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