To use the Blockdaemon RPC API, you need to authenticate your requests with your Blockdeamon API Suite API key. Here's how to do it.

1. Getting an API Key

To start using the Blockdaemon RPC API, you need to get an API key. If you don't have one, you can get a free one by signing up for Blockdaemon. Once you have an API key, you can authenticate your requests.

2. Using Your API Key

Once you have your API key, you can authenticate your requests. Overall, there are three different methods to authenticate the requests, depending on whether you have a new or legacy API key.

2.1. Using Your API Key as a Query Parameter

The easiest way to authenticate a Blockdeamon API Suite request is via a special query parameter:

• parameter: apiKey
• value: YOUR_API_KEY

At the end of any Blockdeamon API Suite endpoint, add the following: ?apiKey=YOUR_API_KEY. See the following cases:

Ethereum Mainnet

https://svc.blockdaemon.com/ethereum/mainnet/native?apiKey=YOUR_API_KEY

HTTP RPC (e.g., Osmosis, Fantom, Base)

https://svc.blockdaemon.com/optimism/mainnet/native/http-rpc?apiKey=YOUR_API_KEY

Tendermint REST (e.g., Polygon, Cronos, Cosmos)

https://svc.blockdaemon.com/polygon/mainnet/native/tendermint-rest/YOUR_METHOD?apiKey=YOUR_API_KEY

Tendermint RPC (e.g., Polygon, Cronos, Cosmos)

https://svc.blockdaemon.com/cronos/mainnet/native/tendermint-rpc?apiKey=YOUR_API_KEY

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Info:

Authentication with a query parameter can be used with any tool - no additional actions are needed.

2.2. Using Your API Key as a Bearer Token

You can authenticate Blockdeamon API Suite API requests by setting YOUR_API_KEY as a bearer token in the authorization header.

2.2.1. Bearer Token in cURL

When working with cURL, use the following code to set your YOUR_API_KEY as a bearer token:

--header 'Authorization: Bearer YOUR_API_KEY'

For example, to retrieve the current block number in Ethereum Mainnet, use the following request: :

curl --request POST 'https://svc.blockdaemon.com/ethereum/mainnet/native' \
--header 'Authorization: Bearer YOUR_API_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "eth_blockNumber",
    "params": []
}

Or, if you prefer to use short options, run the following:

curl -X POST 'https://svc.blockdaemon.com/ethereum/mainnet/native' \
-H 'Authorization: Bearer YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "eth_blockNumber",
    "params": []
}

2.2.2. Bearer Token in Postman

In Postman, you can set YOUR_API_KEY as a bearer token not only for a particular request but also for a collection of requests. To do this, go to a request or collection tab and do the following:

1. Navigate to the Authorization or Auth tab.
2. Select Bearer Token from the Type drop-down menu.
3. Paste YOUR_API_KEY into the Token input box.

Then you can run your request.

2.3. Using Your API Key as an X-API-Key

You can authenticate Blockdeamon API Suite requests by passing your YOUR_API_KEY in the X-API-Key header.

2.3.1. X-API-Key in cURL

When working with cURL, use the following code to set YOUR_API_KEY as a bearer token:

--header 'X-API-Key: YOUR_API_KEY'

For example, to retrieve the current block number in Ethereum Mainnet, use the following request: :

curl --request POST 'https://svc.blockdaemon.com/ethereum/mainnet/native' \
--header 'X-API-Key: YOUR_API_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "eth_blockNumber",
    "params": []
}'

Or, if you prefer to use short options, run the following:

curl -X POST 'https://svc.blockdaemon.com/ethereum/mainnet/native' \
-H 'X-API-Key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "eth_blockNumber",
    "params": []
}

2.3.2. X-API-Key in Postman

In Postman you can set YOUR_API_KEY as an X-API-Key not only for a particular request but also for a collection of requests. Go to a request or collection tab and do the following:

1. Navigate to the Authorization or Auth tab.
2. Select API Key from the Type drop-down menu.
3. Paste your YOUR_API_KEY into the Value input box.
4. Ensure the Add to option is set to Header.

Then you can run your request.

3. Getting the Result

If YOUR_API_KEY is correct, your request will be authorized, and you will get the result. For example, the requests above will give you the current block number in Ethereum Mainnet if authorized:

{
    "jsonrpc": "2.0",
    "id": 1,
    "result": "0xe9c344"
}

If the key is incorrect or missing, you will get this error:

{
    "status": 401,
    "type": "unauthorized",
    "title": "Invalid Token"
}