> ## Documentation Index
> Fetch the complete documentation index at: https://www.helius.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# getFeeForMessage
> Get the fee the network will charge for a particular Message.
## Request Parameters
Base-64 encoded serialized Solana transaction message to calculate the exact fee for.
The commitment level for the request.
* `confirmed`
* `finalized`
The minimum slot that the request can be evaluated at.
## OpenAPI
````yaml openapi/rpc-http/getFeeForMessage.yaml POST /
openapi: 3.1.0
info:
title: Solana RPC API
version: 1.0.0
description: >-
Transaction fee calculator API for estimating exact Solana transaction costs
based on a serialized message, enabling precise gas fee budgeting before
submission.
license:
name: Apache 2.0
url: https://www.apache.org/licenses/LICENSE-2.0.html
servers:
- url: https://mainnet.helius-rpc.com
description: Mainnet RPC endpoint
- url: https://devnet.helius-rpc.com
description: Devnet RPC endpoint
security: []
paths:
/:
post:
tags:
- RPC
summary: getFeeForMessage
description: >
Calculate the exact transaction fee cost for a specific serialized
Solana message.
This fee estimation API provides precise SOL fee calculations based on
the actual
transaction message structure, offering more accurate results than
general fee estimates.
By analyzing the exact operations within the pre-serialized message, it
determines the
exact lamport cost that would be charged. Essential for wallet
applications requiring
precise fee estimation, exchanges calculating withdrawal fees, DApps
planning transaction
budgets, payment processors requiring exact cost calculation, and any
application that
needs to know the precise fee before submitting a transaction to the
Solana network.
operationId: getFeeForMessage
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- jsonrpc
- id
- method
- params
properties:
jsonrpc:
type: string
description: The JSON-RPC protocol version.
enum:
- '2.0'
example: '2.0'
default: '2.0'
id:
type: string
description: A unique identifier for the request.
example: '1'
default: '1'
method:
type: string
description: The name of the RPC method to invoke.
enum:
- getFeeForMessage
example: getFeeForMessage
default: getFeeForMessage
params:
type: array
description: Parameters for the method.
default:
- >-
AQABAgIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAEBAQAA
items:
oneOf:
- type: string
description: >-
Base-64 encoded serialized Solana transaction message
to calculate the exact fee for.
example: >-
AQABAgIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAEBAQAA
- type: object
description: Configuration object containing optional parameters.
properties:
commitment:
type: string
description: The commitment level for the request.
enum:
- confirmed
- finalized
example: finalized
minContextSlot:
type: integer
description: >-
The minimum slot that the request can be evaluated
at.
example: 1000
responses:
'200':
description: Successfully retrieved the fee for the given message.
content:
application/json:
schema:
type: object
properties:
jsonrpc:
type: string
description: The JSON-RPC protocol version.
enum:
- '2.0'
example: '2.0'
id:
type: string
description: Identifier matching the request.
example: '1'
result:
type: object
description: Fee information for the message.
properties:
context:
type: object
description: Context of the response.
properties:
slot:
type: integer
description: The slot at which the fee was calculated.
example: 5068
value:
type: integer
nullable: true
description: >-
Exact transaction fee in lamports (1 SOL =
1,000,000,000 lamports) required to process this
specific message on the network.
example: 5000
'400':
description: Bad Request - Invalid request parameters or malformed request.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
jsonrpc: '2.0'
error:
code: -32602
message: Invalid params
id: '1'
'401':
description: Unauthorized - Invalid or missing API key.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
jsonrpc: '2.0'
error:
code: -32001
message: Unauthorized
id: '1'
'429':
description: Too Many Requests - Rate limit exceeded.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
jsonrpc: '2.0'
error:
code: -32005
message: Too many requests
id: '1'
'500':
description: Internal Server Error - An error occurred on the server.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
jsonrpc: '2.0'
error:
code: -32603
message: Internal error
id: '1'
'503':
description: Service Unavailable - The service is temporarily unavailable.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
jsonrpc: '2.0'
error:
code: -32002
message: Service unavailable
id: '1'
'504':
description: Gateway Timeout - The request timed out.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
example:
jsonrpc: '2.0'
error:
code: -32003
message: Gateway timeout
id: '1'
security:
- ApiKeyQuery: []
components:
schemas:
ErrorResponse:
type: object
properties:
jsonrpc:
type: string
description: The JSON-RPC protocol version.
enum:
- '2.0'
example: '2.0'
error:
type: object
properties:
code:
type: integer
description: The error code.
example: -32602
message:
type: string
description: The error message.
data:
type: object
description: Additional data about the error.
id:
type: string
description: Identifier matching the request.
example: '1'
securitySchemes:
ApiKeyQuery:
type: apiKey
in: query
name: api-key
description: >-
Your Helius API key. You can get one for free in the
[dashboard](https://dashboard.helius.dev/api-keys).
````