# EVM example:
request(
    "POST",
    "/v1/custody/mpc/estimate_fee/",
    {
        "coin": "ETH",
        "amount": 1,
        "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc"
    },
    api_key, api_secret, host
)

# UTXO example:
request(
    "POST",
    "/v1/custody/mpc/estimate_fee/",
    {
        "coin": "XTN",
        "amount": 100000,
        "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
        "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
        "fee": 2.2
    },
    api_key, api_secret, host
)

// EVM example:
coboFetch('POST', '/v1/custody/mpc/estimate_fee/', {
    "coin": "ETH",
    "amount": 1,
    "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc",
}, api_key, api_secret, host)
    .then(res => {
        res.json().then((data)=>{
            console.log(JSON.stringify(data, null, 4));
        })
    }).catch(err => {
        console.log(err)
    });

// UTXO example:
coboFetch('POST', '/v1/custody/mpc/estimate_fee/', {
    "coin": "XTN",
    "amount": 100000,
    "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
    "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
    "fee": 2.2
}, api_key, api_secret, host)
    .then(res => {
        res.json().then((data)=>{
            console.log(JSON.stringify(data, null, 4));
        })
    }).catch(err => {
        console.log(err)
    });

// EVM example:
Request("POST", "/v1/custody/mpc/estimate_fee/", map[string]string{
    "coin": "ETH",
    "amount": 1,
    "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc"
})

// UTXO example:
Request("POST", "/v1/custody/mpc/estimate_fee/", map[string]string{
    "coin": "XTN",
    "amount": 100000,
    "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
    "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
    "fee": 2.2
})

// EVM example:
{
  "success": true,
  "result": {
    "fee_coin": "ETH",
    "fee_decimal": 18,
    "rbf_minimum_fee": 0,
    "slow": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 13349966041,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "average": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 13349966041,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "fast": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 26699932082,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "custom": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    }
  }
}

// UTXO example:
{
  "success": true,
  "result": {
    "fee_coin": "XTN",
    "fee_decimal": 8,
    "rbf_minimum_fee": 0,
    "slow": {
      "fee_per_byte": 2,
      "fee_amount": 632,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "average": {
      "fee_per_byte": 5,
      "fee_amount": 1580,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "fast": {
      "fee_per_byte": 50,
      "fee_amount": 1580,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "custom": {
      "fee_per_byte": 2.2,
      "fee_amount": 695,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    }
  }
}

Account

Get Estimate Fee

This content applies to WaaS 1.0 only. We highly recommend that you upgrade to WaaS 2.0.

This endpoint will simulate a transaction based on the parameters, and obtain the transaction fee from the blockchain. It takes in various parameters such as the coin code, amount, address, gas price, gas limit, fee, and extra parameters. The response includes the fee amount in different levels such as slow, average, fast, and custom. The custom fee corresponds to the fee or gas_price parameter.

POST

custody

mpc

estimate_fee

# EVM example:
request(
    "POST",
    "/v1/custody/mpc/estimate_fee/",
    {
        "coin": "ETH",
        "amount": 1,
        "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc"
    },
    api_key, api_secret, host
)

# UTXO example:
request(
    "POST",
    "/v1/custody/mpc/estimate_fee/",
    {
        "coin": "XTN",
        "amount": 100000,
        "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
        "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
        "fee": 2.2
    },
    api_key, api_secret, host
)

// EVM example:
coboFetch('POST', '/v1/custody/mpc/estimate_fee/', {
    "coin": "ETH",
    "amount": 1,
    "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc",
}, api_key, api_secret, host)
    .then(res => {
        res.json().then((data)=>{
            console.log(JSON.stringify(data, null, 4));
        })
    }).catch(err => {
        console.log(err)
    });

// UTXO example:
coboFetch('POST', '/v1/custody/mpc/estimate_fee/', {
    "coin": "XTN",
    "amount": 100000,
    "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
    "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
    "fee": 2.2
}, api_key, api_secret, host)
    .then(res => {
        res.json().then((data)=>{
            console.log(JSON.stringify(data, null, 4));
        })
    }).catch(err => {
        console.log(err)
    });

// EVM example:
Request("POST", "/v1/custody/mpc/estimate_fee/", map[string]string{
    "coin": "ETH",
    "amount": 1,
    "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc"
})

// UTXO example:
Request("POST", "/v1/custody/mpc/estimate_fee/", map[string]string{
    "coin": "XTN",
    "amount": 100000,
    "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
    "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
    "fee": 2.2
})

// EVM example:
{
  "success": true,
  "result": {
    "fee_coin": "ETH",
    "fee_decimal": 18,
    "rbf_minimum_fee": 0,
    "slow": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 13349966041,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "average": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 13349966041,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "fast": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 26699932082,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "custom": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    }
  }
}

// UTXO example:
{
  "success": true,
  "result": {
    "fee_coin": "XTN",
    "fee_decimal": 8,
    "rbf_minimum_fee": 0,
    "slow": {
      "fee_per_byte": 2,
      "fee_amount": 632,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "average": {
      "fee_per_byte": 5,
      "fee_amount": 1580,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "fast": {
      "fee_per_byte": 50,
      "fee_amount": 1580,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "custom": {
      "fee_per_byte": 2.2,
      "fee_amount": 695,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    }
  }
}

FAQ：How do I query the withdraw fees?

Request

coin

String

required

coin code

amount

Int

transaction amount in decimal places (e.g. one bitcoin is divisible to eight decimal places, and 100000000 represents 1 BTC)

address

String

deposit address

replace_cobo_id

String

Cobo ID of a transaction designated as RBF, this parameter is used when attempting to speed up or drop a previous transaction

from_address

String

from address

For UTXO model, the inputs in the transaction will be selected from the from_address based on either the amount or to_address_details. If this parameter is not provided, the inputs will be selected from the addresses in the current wallet. If the sending amount is greater than the balance, this endpoint will return error code 12007.

For Account model, if the sum of sending amount and transaction fee (gas_price * gas_limit) is greater than the balance of the from_address, the blockchain may return insufficient funds error, and this endpoint will return default transaction fee, please note that the default transaction fee might not be very accurate compared to the fee obtained directly from the blockchain.

to_address_details

Json

list of addresses used for receiving coins associated with the UTXO model; this value must be a JSON string and has a parameter type that fits. Please note that the to_address_details parameter and amount parameter are alternative.

Sample

to_address_details: '[{"to_address": "2N4J1WajwKZKpRtzzUmaW9B5GEqkppqdVY9","amount": "547"},
                      {"to_address": "tb1qycxy8d8jgff8hql09y62smw5s5mrf3ryn2j9lk","amount": "548"}]'

For UTXO model, the parameters from_address, amount, to_address_details, and input_selection will determine the number of bytes in the transaction, and the fee_amount is determined by the fee_per_byte and the number of bytes.

fee

Float

transaction fees per byte; applicable to UTXO model

If specified, the fee_amount in the custom field of the response will be based on the fee parameter and the number of bytes in the transaction.

gas_price

Int

gas price; applicable to account model; unit: wei

gas_limit

Int

gas limit, applicable to account model

extra_parameters

Json

UTXO Model:

input_selection: inputs to be excluded and included in transactions associated with the UTXO model; inputs must be in correspondence with from_address (if specified); it must be a JSON string and has a structure that fits InputSelection
inputs_to_spend: UTXO you want as input. Please note that the length of the list of UTXOs should be less than or equal to 100.
- tx_hash: Transaction tx_hash
- vout_n: UTXO index
inputs_to_exclude: UTXO you don’t want as input
- tx_hash: Transaction tx_hash
- vout_n: UTXO index

Sample

extra_parameters: '{"input_selection":
                     {"inputs_to_spend":[
                       {"tx_hash": "e7ddfa61cc2a78e1661da44b10cdc862256573d2dc0485dc989fb7045ed9032c", "vout_n": 1},
                       {"tx_hash": "eabaee1f1a196b087e78303c6eaaeb9d1166de5f8d85f4ef7872b88bfcd60914", "vout_n": 2}],
                     "inputs_to_exclude":[
                       {"tx_hash": "e7ddfa61cc2a78e1661da44b10cdc862256573d2dc0485dc989fb7045ed9032c", "vout_n": 3},
                       {"tx_hash": "eabaee1f1a196b087e78303c6eaaeb9d1166de5f8d85f4ef7872b88bfcd60914", "vout_n": 4}]
                     }
                   }'

Web3 wallet:

calldata: request data associated with an EVM contract.

Sample

extra_parameters: '{"calldata": "0xa8059cbb000000000000000000000000971948873f869e4517311b190d7eb31e30eba0ef000000000000000000000000000000000000000000000000002386f26fc10000"}'

If specified, the gas_limit in the response will be determined by the calldata.

Response

success

bool

request successful or failed

result

object

Show object

fee_coin

String

Fee coin code

fee_decimal

Int

Fee decimal

slow

object

Show object

fee_per_byte

Int

transaction fees per byte; applicable to the UTXO model

fee_amount

Int

transaction fee; applicable to the UTXO model

gas_price

Int

gas price for account model

gas_limit

Int

gas limit for account model

fee_reserved

Int

The amount that needs to be reserved as a fee. The meaning of this field varies depending on the blockchain:

For certain cryptocurrencies, this field indicates the minimum balance required to be maintained on the address due to chain-specific restrictions.
For some Layer 2 blockchains, this field represents the Layer 1 transaction fee.

average

object

Show object

fee_per_byte

Int

transaction fees per byte; applicable to the UTXO model

fee_amount

Int

transaction fee; applicable to the UTXO model

gas_price

Int

gas price for account model

gas_limit

Int

gas limit for account model

fee_reserved

Int

The amount that needs to be reserved as a fee. The meaning of this field varies depending on the blockchain:

For certain cryptocurrencies, this field indicates the minimum balance required to be maintained on the address due to chain-specific restrictions.
For some Layer 2 blockchains, this field represents the Layer 1 transaction fee.

fast

object

Show object

fee_per_byte

Int

transaction fees per byte; applicable to the UTXO model

fee_amount

Int

transaction fee; applicable to the UTXO model

gas_price

Int

gas price for account model

gas_limit

Int

gas limit for account model

fee_reserved

Int

The amount that needs to be reserved as a fee. The meaning of this field varies depending on the blockchain:

For certain cryptocurrencies, this field indicates the minimum balance required to be maintained on the address due to chain-specific restrictions.
For some Layer 2 blockchains, this field represents the Layer 1 transaction fee.

custom

object

Show object

fee_per_byte

Float

transaction fees per byte; applicable to the UTXO model

fee_amount

Int

transaction fee; applicable to the UTXO model

gas_price

Int

gas price for account model

gas_limit

Int

gas limit for account model

fee_reserved

Int

The amount that needs to be reserved as a fee. The meaning of this field varies depending on the blockchain:

For certain cryptocurrencies, this field indicates the minimum balance required to be maintained on the address due to chain-specific restrictions.
For some Layer 2 blockchains, this field represents the Layer 1 transaction fee.

# EVM example:
request(
    "POST",
    "/v1/custody/mpc/estimate_fee/",
    {
        "coin": "ETH",
        "amount": 1,
        "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc"
    },
    api_key, api_secret, host
)

# UTXO example:
request(
    "POST",
    "/v1/custody/mpc/estimate_fee/",
    {
        "coin": "XTN",
        "amount": 100000,
        "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
        "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
        "fee": 2.2
    },
    api_key, api_secret, host
)

// EVM example:
coboFetch('POST', '/v1/custody/mpc/estimate_fee/', {
    "coin": "ETH",
    "amount": 1,
    "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc",
}, api_key, api_secret, host)
    .then(res => {
        res.json().then((data)=>{
            console.log(JSON.stringify(data, null, 4));
        })
    }).catch(err => {
        console.log(err)
    });

// UTXO example:
coboFetch('POST', '/v1/custody/mpc/estimate_fee/', {
    "coin": "XTN",
    "amount": 100000,
    "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
    "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
    "fee": 2.2
}, api_key, api_secret, host)
    .then(res => {
        res.json().then((data)=>{
            console.log(JSON.stringify(data, null, 4));
        })
    }).catch(err => {
        console.log(err)
    });

// EVM example:
Request("POST", "/v1/custody/mpc/estimate_fee/", map[string]string{
    "coin": "ETH",
    "amount": 1,
    "address": "0x8a73abedb3053b17204b887af6231a8ac35fc2cc"
})

// UTXO example:
Request("POST", "/v1/custody/mpc/estimate_fee/", map[string]string{
    "coin": "XTN",
    "amount": 100000,
    "from_address": "2NB8rYHkrLc54JSpjMM4VMA4GFP8n2eWZdS",
    "address": "2MzxhujoeQZHJ9Dmma93KoWSARofFy5rjxE",
    "fee": 2.2
})

// EVM example:
{
  "success": true,
  "result": {
    "fee_coin": "ETH",
    "fee_decimal": 18,
    "rbf_minimum_fee": 0,
    "slow": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 13349966041,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "average": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 13349966041,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "fast": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 26699932082,
      "gas_limit": 21000,
      "fee_reserved": 0
    },
    "custom": {
      "fee_per_byte": 0,
      "fee_amount": 0,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    }
  }
}

// UTXO example:
{
  "success": true,
  "result": {
    "fee_coin": "XTN",
    "fee_decimal": 8,
    "rbf_minimum_fee": 0,
    "slow": {
      "fee_per_byte": 2,
      "fee_amount": 632,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "average": {
      "fee_per_byte": 5,
      "fee_amount": 1580,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "fast": {
      "fee_per_byte": 50,
      "fee_amount": 1580,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    },
    "custom": {
      "fee_per_byte": 2.2,
      "fee_amount": 695,
      "gas_price": 0,
      "gas_limit": 0,
      "fee_reserved": 0
    }
  }
}

Get Spendable List Get Max Sendable Amount

⌘I

​Request

​Response

Request

Response