> For the complete documentation index, see [llms.txt](/llms.txt).

# Gas API quickstart

This quickstart shows you how to call the Gas API using JavaScript. You can also use a tool such as [curl](https://curl.se/) or [Postman](https://www.postman.com/) to call the REST APIs.

tip

View the [API reference content](/services/reference/gas-api/api-reference/) to view the `curl` command for each API.

## Prerequisites[​](#prerequisites "Direct link to Prerequisites")

- A valid [Web3 API key](/developer-tools/dashboard/get-started/create-api/)and optional [API key secret](/developer-tools/dashboard/how-to/secure-an-api/api-key-secret/).
- [Node.js and npm installed](https://nodejs.org/en/download).

## Initialize a new project directory[​](#initialize-a-new-project-directory "Direct link to Initialize a new project directory")

```
mkdir new_project
cd new_project
npm init -y

```

## Install required packages[​](#install-required-packages "Direct link to Install required packages")

Install the `axios` package:

```
npm install axios

```

Install the [dotenv](/services/how-to/javascript-dotenv/) package:

```
npm install dotenv

```

## Create your `.env` file[​](#create-your-env-file "Direct link to create-your-env-file")

Create a `.env` file at the project root and add the following data:

warning

Do not commit the `.env` file to your repository if it contains sensitive data. You can [create a .gitignore file](/services/how-to/javascript-dotenv/#create-a-gitignore-file)to prevent accidentally committing the file.

.env

```
INFURA_API_KEY=<YOUR-API-KEY>
INFURA_API_KEY_SECRET=<YOUR-API-KEY-SECRET>

```

Replace the Infura project credential placeholders with your own.

note

The `INFURA_API_KEY_SECRET` is optional and only necessary if you are using an [API key secret](/developer-tools/dashboard/how-to/secure-an-api/api-key-secret/) to authenticate requests.

## Create your script[​](#create-your-script "Direct link to Create your script")

The Gas API supports [multiple request formats](/services/reference/gas-api/api-reference/#supported-api-request-formats), and you can call the methods with or without specifying an API key secret.

Create a file (in this example `index.js`):

```
touch index.js

```

Copy the following code into your script:

note

If using a network other than Ethereum Mainnet, update the `chainId` value (`1`) in the code to an alternate [supported network](/services/get-started/endpoints/#gas-api).

- Use an API key only
- Use an API key and API key secret

index.js

```
const axios = require('axios')
require('dotenv').config()

// The chain ID of the supported network
const chainId = 1

;(async () => {
  try {
    const { data } = await axios.get(
      `https://gas.api.infura.io/v3/${process.env.INFURA_API_KEY}/networks/${chainId}/suggestedGasFees`
    )
    console.log('Suggested gas fees:', data)
  } catch (error) {
    console.log('Server responded with:', error)
  }
})()

```

index.js

```
const axios = require('axios')
require('dotenv').config()

const Auth = Buffer.from(
  process.env.INFURA_API_KEY + ':' + process.env.INFURA_API_KEY_SECRET
).toString('base64')

// The chain ID of the supported network
const chainId = 1

;(async () => {
  try {
    const { data } = await axios.get(
      `https://gas.api.infura.io/networks/${chainId}/suggestedGasFees`,
      {
        headers: {
          Authorization: `Basic ${Auth}`,
        },
      }
    )
    console.log('Suggested gas fees:', data)
  } catch (error) {
    console.log('Server responded with:', error)
  }
})()

```

## Run the script[​](#run-the-script "Direct link to Run the script")

```
node index.js

```

The result should look similar to:

```
Suggested gas fees: {
  low: {
    suggestedMaxPriorityFeePerGas: "0.05", // The gas price in gwei
    suggestedMaxFeePerGas: "24.086058416", // The gas price in gwei
    minWaitTimeEstimate: 15000,
    maxWaitTimeEstimate: 30000
  },
  medium: {
    suggestedMaxPriorityFeePerGas: "0.1", // The gas price in gwei
    suggestedMaxFeePerGas: "32.548678862", // The gas price in gwei
    minWaitTimeEstimate: 15000,
    maxWaitTimeEstimate: 45000
  },
  high: {
    suggestedMaxPriorityFeePerGas: "0.3", // The gas price in gwei
    suggestedMaxFeePerGas: "41.161299308", // The gas price in gwei
    minWaitTimeEstimate: 15000,
    maxWaitTimeEstimate: 60000
  },
  estimatedBaseFee: "24.036058416",
  networkCongestion: 0.7143,
  latestPriorityFeeRange: [ "0.1", "20" ],
  historicalPriorityFeeRange: [ "0.007150439", "113" ],
  historicalBaseFeeRange: [ "19.531410688", "36.299069766" ],
  priorityFeeTrend: "down",
  baseFeeTrend: "down"
}

```