> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstack.com/llms.txt
> Use this file to discover all available pages before exploring further.

# estimateFee | TON v3

> The estimateFee endpoint estimates the fee for a transaction on the TON blockchain. Available on TON v3 via Chainstack JSON-RPC nodes.

# Estimate Fee

The `estimateFee` endpoint estimates the fee for a transaction on the TON blockchain. This endpoint allows you to calculate the expected fees before actually sending a transaction.

<Note>
  **TON billing: full (1 RU)**

  This method is always billed as full. See [Request units — TON method scope](/docs/request-units#ton-method-scope).
</Note>

## Parameters

* `address` (string, required) — The address of the smart contract.
* `body` (string, required) — The body of the transaction in base64 format.
* `ignore_chksig` (boolean, optional) — Whether to ignore the signature check. Default: `false`.

## Response

The response includes the estimated fees for both the source and destination of the transaction.

### Source Fees

* `in_fwd_fee` (integer) — The incoming forward fee.
* `storage_fee` (integer) — The storage fee.
* `gas_fee` (integer) — The gas fee.
* `fwd_fee` (integer) — The forward fee.

### Destination Fees

* `in_fwd_fee` (integer) — The incoming forward fee.
* `storage_fee` (integer) — The storage fee.
* `gas_fee` (integer) — The gas fee.
* `fwd_fee` (integer) — The forward fee.

## Use case

The `estimateFee` endpoint is useful for various applications that need to estimate transaction costs on the TON blockchain:

1. Wallet applications can use this to show users the expected cost of a transaction before they send it.
2. Smart contract developers can use this to estimate the cost of deploying or interacting with contracts.
3. DApp developers can integrate this to provide users with accurate fee estimates for transactions.
4. Automated trading systems can use this to factor in transaction costs when making trading decisions.
5. Fee optimization tools can use this endpoint to suggest optimal transaction parameters.


## OpenAPI

````yaml openapi/ton_node_api/v3/estimateFee.json POST /estimateFee
openapi: 3.0.0
info:
  title: TON API
  version: 3.0.0
  description: API for interacting with The Open Network (TON) blockchain
servers:
  - url: >-
      https://ton-mainnet.core.chainstack.com/f2a2411bce1e54a2658f2710cd7969c3/api/v3
security: []
paths:
  /estimateFee:
    post:
      tags:
        - Transaction
      summary: Estimate Fee
      description: Estimates the fee for a transaction on the TON blockchain
      operationId: estimateFee
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                address:
                  type: string
                  description: The address of the smart contract
                  default: EQBVbC7Hu-g3htYXzst8L5ucV76NMzeBK3URJKebN2Y1k55Q
                body:
                  type: string
                  description: The body of the transaction in base64 format
                  default: >-
                    te6ccgEBBAEAwwABRYgAqthdj3fQbw2sL52W+F83OK99GmZvAlbqIklPNm7MayYMAQGcJRnEjp8cFJEdHYEy0LKHHYzifhXgDjogvM4i1RhNr6JL5bGaLxFWgLvL/9Q5K9CsRfVakAbG1JfXmJjD+54vAimpoxdm1XNnAAAAEwADAgFkQgA0XvoMzOTI+7LhqhMUCzQfZ6f1jWBzDLBT90cgmTz0fBE4gAAAAAAAAAAAAAAAAAEDACoAAAAAdGhpcyBpcyBhIHRlc3QgdHg=
                ignore_chksig:
                  type: boolean
                  description: Whether to ignore the signature check
                  default: false
              required:
                - address
                - body
            example:
              address: EQBVbC7Hu-g3htYXzst8L5ucV76NMzeBK3URJKebN2Y1k55Q
              body: >-
                te6ccgEBBAEAwwABRYgAqthdj3fQbw2sL52W+F83OK99GmZvAlbqIklPNm7MayYMAQGcJRnEjp8cFJEdHYEy0LKHHYzifhXgDjogvM4i1RhNr6JL5bGaLxFWgLvL/9Q5K9CsRfVakAbG1JfXmJjD+54vAimpoxdm1XNnAAAAEwADAgFkQgA0XvoMzOTI+7LhqhMUCzQfZ6f1jWBzDLBT90cgmTz0fBE4gAAAAAAAAAAAAAAAAAEDACoAAAAAdGhpcyBpcyBhIHRlc3QgdHg=
              ignore_chksig: false
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                type: object
                properties:
                  source_fees:
                    type: object
                    properties:
                      in_fwd_fee:
                        type: integer
                        description: The incoming forward fee
                      storage_fee:
                        type: integer
                        description: The storage fee
                      gas_fee:
                        type: integer
                        description: The gas fee
                      fwd_fee:
                        type: integer
                        description: The forward fee
                  destination_fees:
                    type: object
                    properties:
                      in_fwd_fee:
                        type: integer
                        description: The incoming forward fee
                      storage_fee:
                        type: integer
                        description: The storage fee
                      gas_fee:
                        type: integer
                        description: The gas fee
                      fwd_fee:
                        type: integer
                        description: The forward fee

````