# starknet_estimateFee > For the complete documentation index, see [llms.txt](/docs/llms.txt). POST https://starknet-mainnet.g.alchemy.com/v2/{apiKey} Estimates the resources required by a given sequence of transactions when applied on a given state. If one of the transactions reverts or fails due to any reason (e.g., validation failure or an internal error), a TRANSACTION_EXECUTION_ERROR is returned. Fees for account transactions are expressed in fri. Reference: https://www.alchemy.com/docs/chains/starknet/starknet-api-endpoints/starknet-estimate-fee ## Parameters | Name | Type | Required | Description | |------|------|----------|-------------| | request | object[] | Yes | The transaction to estimate | | simulation_flags | enum[] | Yes | Describes what parts of the transaction should be executed | | block_id | object or enum | Yes | The hash of the requested block, or number (height) of the requested block, or a block tag, for the block referencing the state or call the transaction on. | ## Result **result** (object[]): The fee estimations ## Code Examples ### cURL ```bash curl --request POST \ --url https://starknet-mainnet.g.alchemy.com/v2/docs-demo \ --header 'Content-Type: application/json' \ --data '{ "jsonrpc": "2.0", "id": 1, "method": "starknet_estimateFee", "params": [ [ { "type": "INVOKE", "sender_address": "string", "calldata": [ "string" ], "version": "0x3", "signature": [ "string" ], "nonce": "string", "resource_bounds": { "l1_gas": { "max_amount": "string", "max_price_per_unit": "string" }, "l2_gas": { "max_amount": "string", "max_price_per_unit": "string" } }, "tip": "string", "paymaster_data": [ "string" ], "account_deployment_data": [ "string" ], "nonce_data_availability_mode": "L1", "fee_data_availability_mode": "L1" } ], [ "SKIP_VALIDATE" ], { "block_hash": "string" } ] }' ``` ### JavaScript ```javascript const options = { method: 'POST', headers: {'Content-Type': 'application/json'}, body: JSON.stringify({ jsonrpc: '2.0', id: 1, method: 'starknet_estimateFee', params: [ [ { type: 'INVOKE', sender_address: 'string', calldata: ['string'], version: '0x3', signature: ['string'], nonce: 'string', resource_bounds: { l1_gas: {max_amount: 'string', max_price_per_unit: 'string'}, l2_gas: {max_amount: 'string', max_price_per_unit: 'string'} }, tip: 'string', paymaster_data: ['string'], account_deployment_data: ['string'], nonce_data_availability_mode: 'L1', fee_data_availability_mode: 'L1' } ], ['SKIP_VALIDATE'], {block_hash: 'string'} ] }) }; fetch('https://starknet-mainnet.g.alchemy.com/v2/docs-demo', options) .then(res => res.json()) .then(res => console.log(res)) .catch(err => console.error(err)); ``` ### Python ```python import requests url = "https://starknet-mainnet.g.alchemy.com/v2/docs-demo" payload = { "jsonrpc": "2.0", "id": 1, "method": "starknet_estimateFee", "params": [[ { "type": "INVOKE", "sender_address": "string", "calldata": ["string"], "version": "0x3", "signature": ["string"], "nonce": "string", "resource_bounds": { "l1_gas": { "max_amount": "string", "max_price_per_unit": "string" }, "l2_gas": { "max_amount": "string", "max_price_per_unit": "string" } }, "tip": "string", "paymaster_data": ["string"], "account_deployment_data": ["string"], "nonce_data_availability_mode": "L1", "fee_data_availability_mode": "L1" } ], ["SKIP_VALIDATE"], { "block_hash": "string" }] } headers = {"Content-Type": "application/json"} response = requests.post(url, json=payload, headers=headers) print(response.text) ``` ### Go ```go package main import ( "fmt" "strings" "net/http" "io" ) func main() { url := "https://starknet-mainnet.g.alchemy.com/v2/docs-demo" payload := strings.NewReader("{\n \"jsonrpc\": \"2.0\",\n \"id\": 1,\n \"method\": \"starknet_estimateFee\",\n \"params\": [\n [\n {\n \"type\": \"INVOKE\",\n \"sender_address\": \"string\",\n \"calldata\": [\n \"string\"\n ],\n \"version\": \"0x3\",\n \"signature\": [\n \"string\"\n ],\n \"nonce\": \"string\",\n \"resource_bounds\": {\n \"l1_gas\": {\n \"max_amount\": \"string\",\n \"max_price_per_unit\": \"string\"\n },\n \"l2_gas\": {\n \"max_amount\": \"string\",\n \"max_price_per_unit\": \"string\"\n }\n },\n \"tip\": \"string\",\n \"paymaster_data\": [\n \"string\"\n ],\n \"account_deployment_data\": [\n \"string\"\n ],\n \"nonce_data_availability_mode\": \"L1\",\n \"fee_data_availability_mode\": \"L1\"\n }\n ],\n [\n \"SKIP_VALIDATE\"\n ],\n {\n \"block_hash\": \"string\"\n }\n ]\n}") req, _ := http.NewRequest("POST", url, payload) req.Header.Add("Content-Type", "application/json") res, _ := http.DefaultClient.Do(req) defer res.Body.Close() body, _ := io.ReadAll(res.Body) fmt.Println(string(body)) } ``` ### Java ```java HttpResponse response = Unirest.post("https://starknet-mainnet.g.alchemy.com/v2/docs-demo") .header("Content-Type", "application/json") .body("{\n \"jsonrpc\": \"2.0\",\n \"id\": 1,\n \"method\": \"starknet_estimateFee\",\n \"params\": [\n [\n {\n \"type\": \"INVOKE\",\n \"sender_address\": \"string\",\n \"calldata\": [\n \"string\"\n ],\n \"version\": \"0x3\",\n \"signature\": [\n \"string\"\n ],\n \"nonce\": \"string\",\n \"resource_bounds\": {\n \"l1_gas\": {\n \"max_amount\": \"string\",\n \"max_price_per_unit\": \"string\"\n },\n \"l2_gas\": {\n \"max_amount\": \"string\",\n \"max_price_per_unit\": \"string\"\n }\n },\n \"tip\": \"string\",\n \"paymaster_data\": [\n \"string\"\n ],\n \"account_deployment_data\": [\n \"string\"\n ],\n \"nonce_data_availability_mode\": \"L1\",\n \"fee_data_availability_mode\": \"L1\"\n }\n ],\n [\n \"SKIP_VALIDATE\"\n ],\n {\n \"block_hash\": \"string\"\n }\n ]\n}") .asString(); ``` ### C# ```csharp using RestSharp; var options = new RestClientOptions("https://starknet-mainnet.g.alchemy.com/v2/docs-demo"); var client = new RestClient(options); var request = new RestRequest(""); request.AddJsonBody("{\n \"jsonrpc\": \"2.0\",\n \"id\": 1,\n \"method\": \"starknet_estimateFee\",\n \"params\": [\n [\n {\n \"type\": \"INVOKE\",\n \"sender_address\": \"string\",\n \"calldata\": [\n \"string\"\n ],\n \"version\": \"0x3\",\n \"signature\": [\n \"string\"\n ],\n \"nonce\": \"string\",\n \"resource_bounds\": {\n \"l1_gas\": {\n \"max_amount\": \"string\",\n \"max_price_per_unit\": \"string\"\n },\n \"l2_gas\": {\n \"max_amount\": \"string\",\n \"max_price_per_unit\": \"string\"\n }\n },\n \"tip\": \"string\",\n \"paymaster_data\": [\n \"string\"\n ],\n \"account_deployment_data\": [\n \"string\"\n ],\n \"nonce_data_availability_mode\": \"L1\",\n \"fee_data_availability_mode\": \"L1\"\n }\n ],\n [\n \"SKIP_VALIDATE\"\n ],\n {\n \"block_hash\": \"string\"\n }\n ]\n}", false); var response = await client.PostAsync(request); Console.WriteLine("{0}", response.Content); ``` ## OpenRPC Method Specification ```yaml name: starknet_estimateFee summary: Estimate the fee for StarkNet transactions description: | Estimates the resources required by a given sequence of transactions when applied on a given state. If one of the transactions reverts or fails due to any reason (e.g., validation failure or an internal error), a TRANSACTION_EXECUTION_ERROR is returned. Fees for account transactions are expressed in fri. params: - name: request description: The transaction to estimate required: true schema: type: array description: | A sequence of transactions to estimate, running each transaction on the state resulting from applying all the previous ones title: Transaction items: title: Broadcasted transaction description: A transaction that has been broadcasted to the network oneOf: - title: Broadcasted invoke transaction description: A transaction that has been broadcasted to the network oneOf: - title: Invoke transaction V3 description: Initiates a transaction from a given account type: object required: - type - sender_address - calldata - version - signature - nonce - resource_bounds - tip - paymaster_data - account_deployment_data - nonce_data_availability_mode - fee_data_availability_mode properties: type: title: Type type: string enum: - INVOKE sender_address: title: Sender address description: A contract address type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ calldata: title: Calldata type: array description: | The data expected by the account's `execute` function (in most use cases, this includes the called contract address and a function selector) items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ version: title: Version description: Version of the transaction scheme type: string enum: - '0x3' - '0x100000000000000000000000000000003' signature: title: Signature description: A transaction signature type: array items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ nonce: title: Nonce description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ resource_bounds: title: Resource bounds description: Resource bounds for the transaction execution type: object required: - l1_gas - l2_gas properties: l1_gas: title: L1 Gas description: The max amount and max price per unit of L1 gas used in this transaction type: object required: - max_amount - max_price_per_unit properties: max_amount: title: Max amount description: The max amount of the resource that can be used in the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ max_price_per_unit: title: Max price per unit description: The max price per unit of this resource for this transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,31})$ l2_gas: title: L2 Gas description: The max amount and max price per unit of L2 gas used in this transaction type: object required: - max_amount - max_price_per_unit properties: max_amount: title: Max amount description: The max amount of the resource that can be used in the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ max_price_per_unit: title: Max price per unit description: The max price per unit of this resource for this transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,31})$ tip: title: Tip description: The tip for the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ paymaster_data: title: Paymaster data type: array description: Data needed to allow the paymaster to pay for the transaction in native tokens items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ account_deployment_data: title: Account deployment data type: array description: Data needed to deploy the account contract from which this transaction will be initiated items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ nonce_data_availability_mode: title: Nonce DA mode description: | The storage domain of the account's nonce (an account has a nonce per DA mode) type: string enum: - L1 - L2 fee_data_availability_mode: title: Fee DA mode description: | The storage domain of the account's balance from which the fee will be charged type: string enum: - L1 - L2 - title: Broadcasted declare transaction description: A transaction that has been broadcasted to the network oneOf: - title: Broadcasted declare transaction V3 description: A transaction that has been broadcasted to the network type: object required: - type - sender_address - compiled_class_hash - version - signature - nonce - class_hash - resource_bounds - tip - paymaster_data - account_deployment_data - nonce_data_availability_mode - fee_data_availability_mode properties: type: title: Declare type: string enum: - DECLARE sender_address: title: Sender address description: | The address of the account contract sending the declaration transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ compiled_class_hash: title: Compiled class hash description: The hash of the Cairo assembly resulting from the Sierra compilation type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ version: title: Version description: Version of the transaction scheme type: string enum: - '0x3' - '0x100000000000000000000000000000003' signature: title: Signature description: A transaction signature type: array items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ nonce: title: Nonce description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ class_hash: title: Class hash description: The hash of the declared class type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ resource_bounds: title: Resource bounds description: Resource bounds for the transaction execution type: object required: - l1_gas - l2_gas properties: l1_gas: title: L1 Gas description: The max amount and max price per unit of L1 gas used in this transaction type: object required: - max_amount - max_price_per_unit properties: max_amount: title: Max amount description: The max amount of the resource that can be used in the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ max_price_per_unit: title: Max price per unit description: The max price per unit of this resource for this transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,31})$ l2_gas: title: L2 Gas description: The max amount and max price per unit of L2 gas used in this transaction type: object required: - max_amount - max_price_per_unit properties: max_amount: title: Max amount description: The max amount of the resource that can be used in the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ max_price_per_unit: title: Max price per unit description: The max price per unit of this resource for this transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,31})$ tip: title: Tip description: The tip for the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ paymaster_data: title: Paymaster data type: array description: Data needed to allow the paymaster to pay for the transaction in native tokens items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ account_deployment_data: title: Account deployment data type: array description: Data needed to deploy the account contract from which this transaction will be initiated items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ nonce_data_availability_mode: title: Nonce DA mode description: | The storage domain of the account's nonce (an account has a nonce per DA mode) type: string enum: - L1 - L2 fee_data_availability_mode: title: Fee DA mode description: | The storage domain of the account's balance from which the fee will be charged type: string enum: - L1 - L2 - title: Broadcasted deploy account transaction description: A transaction that has been broadcasted to the network type: object required: - version - signature - nonce - type - contract_address_salt - constructor_calldata - class_hash - resource_bounds - tip - paymaster_data - account_deployment_data - nonce_data_availability_mode - fee_data_availability_mode properties: version: title: Version description: Version of the transaction scheme type: string enum: - '0x3' - '0x100000000000000000000000000000003' signature: title: Signature description: A transaction signature type: array items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ nonce: title: Nonce description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ type: title: Type type: string enum: - DEPLOY_ACCOUNT contract_address_salt: title: Contract address salt description: The salt for the address of the deployed contract type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ constructor_calldata: title: Constructor calldata type: array description: The parameters passed to the constructor items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ class_hash: title: Class hash description: The hash of the deployed contract's class type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ resource_bounds: title: Resource bounds description: Resource bounds for the transaction execution type: object required: - l1_gas - l2_gas properties: l1_gas: title: L1 Gas description: The max amount and max price per unit of L1 gas used in this transaction type: object required: - max_amount - max_price_per_unit properties: max_amount: title: Max amount description: The max amount of the resource that can be used in the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ max_price_per_unit: title: Max price per unit description: The max price per unit of this resource for this transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,31})$ l2_gas: title: L2 Gas description: The max amount and max price per unit of L2 gas used in this transaction type: object required: - max_amount - max_price_per_unit properties: max_amount: title: Max amount description: The max amount of the resource that can be used in the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ max_price_per_unit: title: Max price per unit description: The max price per unit of this resource for this transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,31})$ tip: title: Tip description: The tip for the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,15})$ paymaster_data: title: Paymaster data type: array description: Data needed to allow the paymaster to pay for the transaction in native tokens items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ account_deployment_data: title: Account deployment data type: array description: Data needed to deploy the account contract from which this transaction will be initiated items: title: Field element description: A field element. Represented by at most 63 hex digits type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ nonce_data_availability_mode: title: Nonce DA mode description: The storage domain of the account's nonce (an account has a nonce per DA mode) type: string enum: - L1 - L2 fee_data_availability_mode: title: Fee DA mode description: The storage domain of the account's balance from which the fee will be charged type: string enum: - L1 - L2 - name: simulation_flags description: Describes what parts of the transaction should be executed required: true schema: type: array items: title: Simulation flag for estimate fee description: | Flags that indicate how to simulate a given transaction. By default, the sequencer behavior is replicated locally type: string enum: - SKIP_VALIDATE - name: block_id description: | The hash of the requested block, or number (height) of the requested block, or a block tag, for the block referencing the state or call the transaction on. required: true schema: title: Block id description: Block hash, number or tag oneOf: - title: Block hash type: object required: - block_hash properties: block_hash: title: Block hash description: The hash identifying a block type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ - title: Block number type: object required: - block_number properties: block_number: title: Block number description: The block's number (its height) type: integer minimum: 0 - title: Block tag description: A tag specifying a dynamic reference to a block type: string enum: - latest - pending result: name: result description: The fee estimations schema: title: Estimation type: array description: | A sequence of fee estimations where the i'th estimate corresponds to the i'th transaction items: title: Fee estimation type: object required: - gas_consumed - gas_price - data_gas_consumed - data_gas_price - overall_fee - unit properties: gas_consumed: title: Gas consumed description: The Ethereum gas consumption of the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ gas_price: title: Gas price description: | The gas price (in wei or fri, depending on the tx version) that was used in the cost estimation type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ data_gas_consumed: title: Data gas consumed description: The Ethereum data gas consumption of the transaction type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ data_gas_price: title: Data gas price description: | The data gas price (in wei or fri, depending on the tx version) that was used in the cost estimation type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ overall_fee: title: Overall fee description: | The estimated fee for the transaction (in wei or fri, depending on the tx version), equals to gas_consumed * gas_price + data_gas_consumed * data_gas_price type: string pattern: ^0x(0|[a-fA-F1-9]{1}[a-fA-F0-9]{0,62})$ unit: title: Fee unit description: Units in which the fee is given type: string enum: - WEI - FRI ```