Protocol Parameters

Protocol parameters define the network's rules — fee calculations, size limits, deposits, and Plutus execution costs. The transaction builder fetches these automatically, but you can also query them directly.

Query Parameters

import {  } from "@evolution-sdk/evolution"

const  = ({
  : "preprod",
  : { : "blockfrost", : "https://cardano-preprod.blockfrost.io/api/v0", : ..! },
  : { : "seed", : ..!, : 0 }
})

const  = await .()

.("Min fee coefficient:", .)
.("Min fee constant:", .)
.("Max tx size:", .)
.("Key deposit:", .)
.("Pool deposit:", .)

Key Parameters

Parameter	Description	Typical Value
`minFeeA`	Fee per byte coefficient	44
`minFeeB`	Base fee constant	155381
`maxTxSize`	Maximum transaction size (bytes)	16384
`keyDeposit`	Stake key registration deposit	2000000 (2 ADA)
`poolDeposit`	Pool registration deposit	500000000 (500 ADA)
`coinsPerUtxoByte`	Minimum ADA per UTxO byte	4310
`collateralPercentage`	Collateral percentage for scripts	150
`priceMem`	Plutus memory cost coefficient	0.0577
`priceStep`	Plutus CPU cost coefficient	0.0000721

Override in Build Options

You can provide custom protocol parameters when building transactions:

import { , ,  } from "@evolution-sdk/evolution"

const  = ({
  : "preprod",
  : { : "blockfrost", : "https://cardano-preprod.blockfrost.io/api/v0", : ..! },
  : { : "seed", : ..!, : 0 }
})

declare const : any

const  = await 
  .()
  .({
    : .("addr_test1vrm9x2dgvdau8vckj4duc89m638t8djmluqw5pdrFollw8qd9k63"),
    : .(2_000_000n)
  })
  .({ :  })

Next Steps

Transaction Status — Check confirmation status
UTxOs — Query unspent outputs

Protocol Parameters

Protocol Parameters

Query Parameters

Key Parameters

Override in Build Options

Next Steps

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