> ## Documentation Index > Fetch the complete documentation index at: https://developers.circle.com/llms.txt > Use this file to discover all available pages before exploring further. # Estimate fee for a contract execution transaction > Estimates gas fees that will be incurred for a contract execution transaction, given its ABI parameters and blockchain. ## OpenAPI ````yaml openapi/user-controlled-wallets.yaml post /v1/w3s/transactions/contractExecution/estimateFee openapi: 3.0.3 info: version: '1.0' title: User-Controlled Wallets description: User-Controlled Wallets API documentation. servers: - url: https://api.circle.com security: - BearerAuth: [] tags: - name: Social/ Email Authentication - name: PIN Authentication - name: Users - name: Wallets - name: Transactions - name: Token Lookup - name: Signing paths: /v1/w3s/transactions/contractExecution/estimateFee: post: tags: - Transactions summary: Estimate fee for a contract execution transaction description: >- Estimates gas fees that will be incurred for a contract execution transaction, given its ABI parameters and blockchain. operationId: createTransactionEstimateFee parameters: - $ref: '#/components/parameters/XUserToken' - $ref: '#/components/parameters/XRequestId' requestBody: $ref: '#/components/requestBodies/EstimateContractExecutionTransactionFee' responses: '200': content: application/json: schema: $ref: '#/components/schemas/EstimateTransactionFee' description: Transaction fee estimated headers: X-Request-Id: $ref: '#/components/headers/XRequestId' '400': $ref: '#/components/responses/DefaultError' '401': $ref: '#/components/responses/NotAuthorized' '404': $ref: '#/components/responses/NotFound' security: - BearerAuth: [] components: parameters: XUserToken: name: X-User-Token description: Unique system generated JWT session token for specific user. required: true in: header schema: type: string XRequestId: name: X-Request-Id in: header description: > Developer-provided identifier for this request, used for tracing requests in Wallets API logs and the Developer Console, and when communicating with Circle Support. **Must be a UUID to appear in logs.** Non-UUID values are accepted by the API but are ignored by logging and tracing systems. schema: $ref: '#/components/schemas/XRequestId' requestBodies: EstimateContractExecutionTransactionFee: content: application/json: schema: title: EstimateContractExecutionTransactionFeeRequest type: object required: - contractAddress properties: abiFunctionSignature: $ref: '#/components/schemas/AbiFunctionSignature' abiParameters: $ref: '#/components/schemas/AbiParameters' callData: $ref: '#/components/schemas/CallData' amount: $ref: '#/components/schemas/Amount' blockchain: $ref: '#/components/schemas/ContractExecutionBlockchain' contractAddress: $ref: '#/components/schemas/ContractAddress' sourceAddress: $ref: '#/components/schemas/SourceAddress' walletId: $ref: '#/components/schemas/WalletId' description: Estimate transaction fee request required: true schemas: EstimateTransactionFee: title: EstimateTransactionFeeResponse type: object required: - data properties: data: type: object properties: high: $ref: '#/components/schemas/TransactionFee' low: $ref: '#/components/schemas/TransactionFee' medium: $ref: '#/components/schemas/TransactionFee' callGasLimit: $ref: '#/components/schemas/CallGasLimit' verificationGasLimit: $ref: '#/components/schemas/VerificationGasLimit' preVerificationGas: $ref: '#/components/schemas/PreVerificationGas' XRequestId: type: string format: uuid description: >- A unique identifier, which can be helpful for identifying a request when communicating with Circle support. example: 2adba88e-9d63-44bc-b975-9b6ae3440dde AbiFunctionSignature: title: AbiFunctionSignature type: string description: "The contract ABI function signature or\_`callData`\_field is required for interacting with the smart contract. The ABI function signature cannot be used simultaneously with\_`callData`. e.g. burn(uint256)" example: burn(uint256) AbiParameters: title: AbiParameters type: array items: anyOf: - type: string - type: integer - type: boolean - type: array items: {} description: "The contract ABI function signature parameters for executing the contract interaction. Supported parameter types include string, integer, boolean, and array. These parameters should be used exclusively with the abiFunctionSignature and cannot be used with\_`callData`." example: - '100' - '1' CallData: title: CallData type: string description: "The raw transaction data, must be an even-length hexadecimal string with the\_`0x`\_prefix, to be executed. It is important to note that the usage of\_`callData`\_is mutually exclusive with the\_`abiFunctionSignature`\_and\_`abiParameters`. Therefore,\_`callData`\_cannot be utilized simultaneously with either\_`abiFunctionSignature`\_or\_`abiParameters`." example: >- 0xcdcd77c000000000000000000000000000000000000000000000000000000000000000450000000000000000000000000000000000000000000000000000000000000001 Amount: title: Amount type: string description: >- The amount of native token that will be sent to the contract abi execution. Optional field for payable api only, if not provided, no native token will be sent. example: '1.0' ContractExecutionBlockchain: title: ContractExecutionBlockchain type: string description: > Blockchain associated with the contract execution transaction. Required when either of `walletAddress` or `sourceAddress` is provided. The `blockchain` and `walletId` fields are mutually exclusive. enum: - ETH - ETH-SEPOLIA - AVAX - AVAX-FUJI - MATIC - MATIC-AMOY - ARB - ARB-SEPOLIA - UNI - UNI-SEPOLIA - BASE - BASE-SEPOLIA - OP - OP-SEPOLIA - ARC-TESTNET - MONAD - MONAD-TESTNET example: MATIC-AMOY ContractAddress: title: ContractAddress description: The blockchain address of the contract to be executed. type: string example: '0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48' SourceAddress: type: string description: > Source address of the transaction. Required along with `blockchain` if `walletId` is not provided. The `sourceAddress` and `walletId` fields are mutually exclusive. example: '0x1bf9ad0cc2ad298c69a2995aa806ee832788218c' WalletId: title: WalletId type: string format: uuid description: | Unique system generated identifier of the wallet. For contract deploys this wallet ID will be used as the source. example: a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11 TransactionFee: type: object properties: gasLimit: $ref: '#/components/schemas/GasLimit' gasPrice: $ref: '#/components/schemas/GasPrice' maxFee: $ref: '#/components/schemas/MaxFee' priorityFee: $ref: '#/components/schemas/PriorityFee' baseFee: $ref: '#/components/schemas/BaseFee' networkFee: $ref: '#/components/schemas/NetworkFee' networkFeeRaw: $ref: '#/components/schemas/NetworkFeeRaw' l1Fee: $ref: '#/components/schemas/L1Fee' CallGasLimit: title: CallGasLimit type: string description: >- One of ERC-4337 gas fields. The amount of gas to allocate for the main execution call. Only in smart contract account estimation response. example: '69222' VerificationGasLimit: title: VerificationGasLimit type: string description: >- One of ERC-4337 gas fields. The amount of gas to allocate for the verification step. Only in smart contract account estimation response. example: '56863' PreVerificationGas: title: PreVerificationGas type: string description: >- One of ERC-4337 gas fields. The amount of gas to pay to compensate the bundler for pre-verification execution and call data. Only in smart contract account estimation response. example: '44112' Error: title: Error type: object required: - code - message properties: code: type: integer description: Code that corresponds to the error. message: type: string description: Message that describes the error. GasLimit: type: string description: > The maximum units of gas to use for the transaction. Required if `feeLevel` is not provided. Estimates for this limit can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. An insufficient gas limit may cause the transaction to fail on-chain. Use this field with care when manually providing values. GasLimit override (only supported for EOA wallets): Using `gasLimit` together with `feeLevel`, the provided `gasLimit` will override the estimation's gasLimit. example: '21000' GasPrice: type: string description: > For blockchains without EIP-1559 support, the maximum price of gas, in gwei, to use per each unit of gas (see `gasLimit`). Requires `gasLimit`. Cannot be used with `feeLevel`, `priorityFee`, or `maxFee`. Estimates for this fee can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. The wallet service enforces a dynamic minimum `gasPrice` based on current network conditions. Requests specifying a `gasPrice` below this minimum will be rejected MaxFee: type: string example: '5.935224468' description: > For blockchains with EIP-1559 support, the maximum price per unit of gas (see `gasLimit`), in gwei. Requires `priorityFee`, and `gasLimit` to be present. Cannot be used with `feeLevel` or `gasPrice`. Estimates for this fee can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. PriorityFee: type: string example: '1.022783914' description: > For blockchains with EIP-1559 support, the “tip”, in gwei, to add to the base fee as an incentive for validators. Please note that the `maxFee` and `gasLimit` parameters are required alongside the `priorityFee`. The `feeLevel` and `gasPrice` parameters cannot be used with the `priorityFee`. Estimations for this fee can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. The wallet service enforces a dynamic minimum `priorityFee` based on current network conditions. Requests specifying a `priorityFee` below this minimum will be rejected BaseFee: type: string example: '1.022783914' description: > For blockchains with EIP-1559 support, the estimated base fee represents the minimum fee required for a transaction to be included in a block on the blockchain. It is measured in gwei and compensates for the computational resources validators consume to process the transaction. The base fee is supplemented by a separate "tip" called the priority fee, which acts as an extra incentive for validators to prioritize the transaction. The priority fee is added to the base fee to calculate the final transaction fee. NetworkFee: type: string example: '0.0001246397138' description: > The estimated network fee is the maximum amount of cryptocurrency (such as ETH, ARB, or SOL) that you will pay for your transaction. This fee depends on the parameters you set, including Gas Limit, Priority Fee, and Max Fee. It compensates for the computational resources that validators consume to process the transaction. It is measured in native token such as ETH, SOL. For blockchains with L1 data fees such as OP/BASE, the network fee is a combination of the Execution Gas Fee and the L1 Data Fee. Each blockchain might use different formula for network fee. Refer to each specific blockchain's documentation to understand how `networkFee` is calculated. NetworkFeeRaw: type: string example: '0.0001246397138' description: > Similar to `networkFee`, `networkFeeRaw` is an estimation with lower buffer and thus should be closer to the actual on-chain expense. This field will only be returned in the estimation response. L1Fee: type: string example: '0.000000000000140021' description: > This fee represents the Layer 1 (L1) rollup charge associated with transactions on Layer 2 blockchains. The amount is expressed in the native currency, such as ETH. This field is relevant for Layer 2 blockchains utilizing a rollup mechanism and for specific account types, such as externally owned accounts (EOAs) on the Optimism (OP) blockchain. headers: XRequestId: description: > Developer-provided header parameter or Circle-generated universally unique identifier (UUID v4). Useful for identifying a specific request when communicating with Circle Support. schema: $ref: '#/components/schemas/XRequestId' responses: DefaultError: content: application/json: schema: $ref: '#/components/schemas/Error' description: Error response headers: X-Request-Id: $ref: '#/components/headers/XRequestId' NotAuthorized: content: application/json: schema: type: object title: NotAuthorizedResponse required: - code - message properties: code: type: integer description: Code that corresponds to the error. message: type: string description: Message that describes the error. example: code: 401 message: Malformed authorization. description: >- Request has not been applied because it lacks valid authentication credentials. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' NotFound: content: application/json: schema: type: object title: NotFoundResponse required: - code - message properties: code: type: integer description: Code that corresponds to the error. message: type: string description: Message that describes the error. example: code: 404 message: Not found. description: Specified resource was not found. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: PREFIX:ID:SECRET description: >- Circle's API Keys are formatted in the following structure "PREFIX:ID:SECRET". All three parts are required to make a successful request. ````