---
title: JSON-RPC APIs
description: JSON-RPC APIs guide for Polkadot Hub, covering supported methods, parameters, and examples for interacting with the chain.
categories:
- Reference
url: https://docs.polkadot.com/smart-contracts/for-eth-devs/json-rpc-apis/
word_count: 4012
token_estimate: 9712
version_hash: sha256:f07175cbe34280c5145ffeabf00bff70df102d7435c9d0c07700f8eb19cd69bc
last_updated: '2026-06-04T16:08:37+00:00'
---

# JSON-RPC APIs

## Introduction

Polkadot Hub provides Ethereum compatibility through its JSON-RPC interface, allowing developers to interact with the chain using familiar Ethereum tooling and methods. This document outlines the supported [Ethereum JSON-RPC methods](https://ethereum.org/developers/docs/apis/json-rpc/#json-rpc-methods) and provides examples of how to use them.

This guide uses the Polkadot Hub TestNet endpoint:

```text
https://services.polkadothub-rpc.com/testnet
```

## Available Methods

### eth_accounts

Returns a list of addresses owned by the client. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_accounts).

**Parameters**:

None.

**Example**:

```bash title="eth_accounts"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_accounts",
    "params":[],
    "id":1
}'
```

---

### eth_blockNumber

Returns the number of the most recent block. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_blocknumber).

**Parameters**:

None.

**Example**:

```bash title="eth_blockNumber"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_blockNumber",
    "params":[],
    "id":1
}'
```

---

### eth_call

Executes a new message call immediately without creating a transaction. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_call).

**Parameters**:

- **`transaction` ++"object"++**: The transaction call object.
    - **`to` ++"string"++**: Recipient address of the call. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`data` ++"string"++**: Hash of the method signature and encoded parameters. Must be a [data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`from` ++"string"++**: (Optional) Sender's address for the call. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`gas` ++"string"++**: (Optional) Gas limit to execute the call. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`gasPrice` ++"string"++**: (Optional) Gas price per unit of gas. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`value` ++"string"++**: (Optional) Value in wei to send with the call. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
- **`blockValue` ++"string"++**: (Optional) Block tag or block number to execute the call at. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).
- **`stateOverrides` ++"object"++**: (Optional) A mapping of addresses to state overrides. Allows temporary modification of account state for the duration of the call without persisting changes on-chain. Conforms to the [Geth state override specification](https://geth.ethereum.org/docs/interacting-with-geth/rpc/ns-eth#state-override-set).
    - **Key**: Account address as a hex string (e.g., `"0x1234..."`)
    - **Value**: An object with the following optional fields:
        - **`balance` ++"string"++**: (Optional) Fake balance to set for the account. Must be a quantity string.
        - **`nonce` ++"string"++**: (Optional) Fake nonce to set for the account. Must be a quantity string.
        - **`code` ++"string"++**: (Optional) Fake bytecode to inject at the account address. On Polkadot Hub, this field accepts both EVM bytecode and PolkaVM (PVM) bytecode, which is detected automatically via magic bytes.
        - **`state` ++"object"++**: (Optional) Completely replaces all storage slots for the account. A mapping of storage keys to storage values (both as 32-byte hex strings). Unspecified slots are zeroed. Mutually exclusive with `stateDiff`.
        - **`stateDiff` ++"object"++**: (Optional) Patches only the specified storage slots, leaving all other slots unchanged. A mapping of storage keys to storage values (both as 32-byte hex strings). Mutually exclusive with `state`.
        - **`movePrecompileToAddress` ++"string"++**: (Optional) Accepted for Geth compatibility but has no effect, as Polkadot Hub does not use relocatable precompile addresses.

**Example**:

=== "Basic"

    ```bash
    curl -X POST https://services.polkadothub-rpc.com/testnet \
    -H "Content-Type: application/json" \
    --data '{
        "jsonrpc":"2.0",
        "method":"eth_call",
        "params":[{
            "to": "INSERT_RECIPIENT_ADDRESS",
            "data": "INSERT_ENCODED_CALL"
        }, "INSERT_BLOCK_VALUE"],
        "id":1
    }'
    ```

    Ensure to replace `INSERT_RECIPIENT_ADDRESS`, `INSERT_ENCODED_CALL`, and `INSERT_BLOCK_VALUE` with the appropriate values.

=== "With state overrides"

    ```bash
    curl -X POST https://services.polkadothub-rpc.com/testnet \
    -H "Content-Type: application/json" \
    --data '{
        "jsonrpc":"2.0",
        "method":"eth_call",
        "params":[{
            "to": "INSERT_RECIPIENT_ADDRESS",
            "data": "INSERT_ENCODED_CALL"
        }, "latest", {
            "INSERT_ADDRESS": {
                "balance": "0xDE0B6B3A7640000"
            }
        }],
        "id":1
    }'
    ```

    In this example, the account at `INSERT_ADDRESS` is temporarily assigned a balance of 1 native token (10^18 in its smallest denomination) for the duration of the call. Ensure to replace `INSERT_RECIPIENT_ADDRESS`, `INSERT_ENCODED_CALL`, and `INSERT_ADDRESS` with the appropriate values.

!!! note "Differences from Ethereum"
    Polkadot Hub's `eth_call` state overrides are fully compatible with the [Geth state override specification](https://geth.ethereum.org/docs/interacting-with-geth/rpc/ns-eth#state-override-set). One Polkadot-specific extension is that the `code` field accepts both EVM bytecode and PolkaVM (PVM) bytecode, detected automatically via magic bytes at the start of the blob.

---

### eth_chainId

Returns the chain ID used for signing transactions. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_chainid).

**Parameters**:

None.

**Example**:

```bash title="eth_chainId"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_chainId",
    "params":[],
    "id":1
}'
```

---

### eth_estimateGas

Estimates gas required for a transaction. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_estimategas).

**Parameters**:

- **`transaction` ++"object"++**: The transaction call object.
    - **`to` ++"string"++**: Recipient address of the call. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`data` ++"string"++**: Hash of the method signature and encoded parameters. Must be a [data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`from` ++"string"++**: (Optional) Sender's address for the call. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`gas` ++"string"++**: (Optional) Gas limit to execute the call. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`gasPrice` ++"string"++**: (Optional) Gas price per unit of gas. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`value` ++"string"++**: (Optional) Value in wei to send with the call. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
- **`blockValue` ++"string"++**: (Optional) Block tag or block number to execute the call at. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).

**Example**:

```bash title="eth_estimateGas"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_estimateGas",
    "params":[{
        "to": "INSERT_RECIPIENT_ADDRESS",
        "data": "INSERT_ENCODED_FUNCTION_CALL"
    }],
    "id":1
}'
```

Ensure to replace the `INSERT_RECIPIENT_ADDRESS` and `INSERT_ENCODED_CALL` with the proper values.

---

### eth_gasPrice

Returns the current gas price in Wei. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_gasprice).

**Parameters**:

None.

**Example**:

```bash title="eth_gasPrice"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_gasPrice",
    "params":[],
    "id":1
}'
```

---

### eth_getBalance

Returns the balance of a given address. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getbalance).

**Parameters**:

- **`address` ++"string"++**: Address to query balance. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
- **`blockValue` ++"string"++**: (Optional) The block value to be fetched. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).

**Example**:

```bash title="eth_getBalance"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getBalance",
    "params":["INSERT_ADDRESS", "INSERT_BLOCK_VALUE"],
    "id":1
}'
```

Ensure to replace the `INSERT_ADDRESS` and `INSERT_BLOCK_VALUE` with the proper values.

---

### eth_getBlockByHash

Returns information about a block by its hash. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getblockbyhash).

**Parameters**:

- **`blockHash` ++"string"++**: The hash of the block to retrieve. Must be a [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
- **`fullTransactions` ++"boolean"++**: If `true`, returns full transaction details; if `false`, returns only transaction hashes.

**Example**:

```bash title="eth_getBlockByHash"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockByHash",
    "params":["INSERT_BLOCK_HASH", INSERT_BOOLEAN],
    "id":1
}'
```

Ensure to replace the `INSERT_BLOCK_HASH` and `INSERT_BOOLEAN` with the proper values.

---

### eth_getBlockByNumber

Returns information about a block by its number. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getblockbynumber).

**Parameters**:

- **`blockValue` ++"string"++**: (Optional) The block value to be fetched. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).
- **`fullTransactions` ++"boolean"++**: If `true`, returns full transaction details; if `false`, returns only transaction hashes.

**Example**:

```bash title="eth_getBlockByNumber"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockByNumber",
    "params":["INSERT_BLOCK_VALUE", INSERT_BOOLEAN],
    "id":1
}'
```

Ensure to replace the `INSERT_BLOCK_VALUE` and `INSERT_BOOLEAN` with the proper values.

---

### eth_getBlockTransactionCountByNumber

Returns the number of transactions in a block from a block number. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getblocktransactioncountbynumber).

**Parameters**:

- **`blockValue` ++"string"++**: The block value to be fetched. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).

**Example**:

```bash title="eth_getBlockTransactionCountByNumber"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockTransactionCountByNumber",
    "params":["INSERT_BLOCK_VALUE"],
    "id":1
}'
```

Ensure to replace the `INSERT_BLOCK_VALUE` with the proper values.

---

### eth_getBlockTransactionCountByHash

Returns the number of transactions in a block from a block hash. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getblocktransactioncountbyhash).

**Parameters**:

- **`blockHash` ++"string"++**: The hash of the block to retrieve. Must be a [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.

**Example**:

```bash title="eth_getBlockTransactionCountByHash"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getBlockTransactionCountByHash",
    "params":["INSERT_BLOCK_HASH"],
    "id":1
}'
```

Ensure to replace the `INSERT_BLOCK_HASH` with the proper values.

---

### eth_getCode

Returns the code at a given address. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getcode).

**Parameters**:

- **`address` ++"string"++**: Contract or account address to query code. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
- **`blockValue` ++"string"++**: (Optional) The block value to be fetched. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).

**Example**:

```bash title="eth_getCode"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getCode",
    "params":["INSERT_ADDRESS", "INSERT_BLOCK_VALUE"],
    "id":1
}'
```

Ensure to replace the `INSERT_ADDRESS` and `INSERT_BLOCK_VALUE` with the proper values.

---

### eth_getLogs

Returns an array of all logs matching a given filter object. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getlogs).

**Parameters**:

- **`filter` ++"object"++**: The filter object.
    - **`fromBlock` ++"string"++**: (Optional) Block number or tag to start from. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).
    - **`toBlock` ++"string"++**: (Optional) Block number or tag to end at. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).
    - **`address` ++"string" or "array of strings"++**: (Optional) Contract address or a list of addresses from which to get logs. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`topics` ++"array of strings"++**: (Optional) Array of topics for filtering logs. Each topic can be a single [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string or an array of such strings (meaning OR).
    - **`blockhash` ++"string"++**: (Optional) Hash of a specific block. Cannot be used with `fromBlock` or `toBlock`. Must be a [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.

**Example**:

```bash title="eth_getLogs"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getLogs",
    "params":[{
        "fromBlock": "latest",
        "toBlock": "latest"
    }],
    "id":1
}'
```

---

### eth_getStorageAt

Returns the value from a storage position at a given address. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_getstorageat).

**Parameters**:

- **`address` ++"string"++**: Contract or account address to query code. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
- **`storageKey` ++"string"++**: Position in storage to retrieve data from. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
- **`blockValue` ++"string"++**: (Optional) The block value to be fetched. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).

**Example**:

```bash title="eth_getStorageAt"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getStorageAt",
    "params":["INSERT_ADDRESS", "INSERT_STORAGE_KEY", "INSERT_BLOCK_VALUE"],
    "id":1
}'
```

Ensure to replace the `INSERT_ADDRESS`, `INSERT_STORAGE_KEY`, and `INSERT_BLOCK_VALUE` with the proper values.

---

### eth_getTransactionCount

Returns the number of transactions sent from an address (nonce). [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_gettransactioncount).

**Parameters**:

- **`address` ++"string"++**: Address to query balance. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
- **`blockValue` ++"string"++**: (Optional) The block value to be fetched. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).

**Example**:

```bash title="eth_getTransactionCount"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getTransactionCount",
    "params":["INSERT_ADDRESS", "INSERT_BLOCK_VALUE"],
    "id":1
}'
```

Ensure to replace the `INSERT_ADDRESS` and `INSERT_BLOCK_VALUE` with the proper values.

---

### eth_getTransactionByHash

Returns information about a transaction by its hash. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_gettransactionbyhash).

**Parameters**:

- **`transactionHash` ++"string"++**: The hash of the transaction. Must be a [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.

**Example**:

```bash title="eth_getTransactionByHash"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getTransactionByHash",
    "params":["INSERT_TRANSACTION_HASH"],
    "id":1
}'
```

Ensure to replace the `INSERT_TRANSACTION_HASH` with the proper values.

---

### eth_getTransactionByBlockNumberAndIndex

Returns information about a transaction by block number and transaction index. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_gettransactionbyblocknumberandindex).

**Parameters**:

- **`blockValue` ++"string"++**: The block value to be fetched. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).
- **`transactionIndex` ++"string"++**: The index of the transaction in the block. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.

**Example**:

```bash title="eth_getTransactionByBlockNumberAndIndex"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getTransactionByBlockNumberAndIndex",
    "params":["INSERT_BLOCK_VALUE", "INSERT_TRANSACTION_INDEX"],
    "id":1
}'
```

Ensure to replace the `INSERT_BLOCK_VALUE` and `INSERT_TRANSACTION_INDEX` with the proper values.

---

### eth_getTransactionByBlockHashAndIndex

Returns information about a transaction by block hash and transaction index. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_gettransactionbyblockhashandindex).

**Parameters**:

- **`blockHash` ++"string"++**: The hash of the block. Must be a [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
- **`transactionIndex` ++"string"++**: The index of the transaction in the block. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.

**Example**:

```bash title="eth_getTransactionByBlockHashAndIndex"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getTransactionByBlockHashAndIndex",
    "params":["INSERT_BLOCK_HASH", "INSERT_TRANSACTION_INDEX"],
    "id":1
}'
```

Ensure to replace the `INSERT_BLOCK_HASH` and `INSERT_TRANSACTION_INDEX` with the proper values.

---

### eth_getTransactionReceipt

Returns the receipt of a transaction by transaction hash. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_gettransactionreceipt).

**Parameters**:

- **`transactionHash` ++"string"++**: The hash of the transaction. Must be a [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.

**Example**:

```bash title="eth_getTransactionReceipt"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_getTransactionReceipt",
    "params":["INSERT_TRANSACTION_HASH"],
    "id":1
}'
```

Ensure to replace the `INSERT_TRANSACTION_HASH` with the proper values.

---

### eth_maxPriorityFeePerGas

Returns an estimate of the current priority fee per gas, in Wei, to be included in a block.

**Parameters**:

None.

**Example**:

```bash title="eth_maxPriorityFeePerGas"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_maxPriorityFeePerGas",
    "params":[],
    "id":1
}'
```

---

### eth_sendRawTransaction

Submits a raw transaction. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_sendrawtransaction).

**Parameters**:

- **`callData` ++"string"++**: Signed transaction data. Must be a [data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.

**Example**:

```bash title="eth_sendRawTransaction"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_sendRawTransaction",
    "params":["INSERT_CALL_DATA"],
    "id":1
}'
```

Ensure to replace the `INSERT_CALL_DATA` with the proper values.

---

### eth_sendTransaction

Creates and sends a new transaction. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_sendtransaction).

**Parameters**:

- **`transaction` ++"object"++**: The transaction object.
    - **`from` ++"string"++**: Address sending the transaction. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`to` ++"string"++**: (Optional) Recipient address. No need to provide this value when deploying a contract. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`gas` ++"string"++**: (optional, default: `90000`) gas limit for execution. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`gasPrice` ++"string"++**: (Optional) Gas price per unit. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`value` ++"string"++**: (Optional) Amount of Ether to send. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`data` ++"string"++**: (Optional) Contract bytecode or encoded method call. Must be a [data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`nonce` ++"string"++**: (Optional) Transaction nonce. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.

**Example**:

```bash title="eth_sendTransaction"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_sendTransaction",
    "params":[{
        "from": "INSERT_SENDER_ADDRESS",
        "to": "INSERT_RECIPIENT_ADDRESS",
        "gas": "INSERT_GAS_LIMIT",
        "gasPrice": "INSERT_GAS_PRICE",
        "value": "INSERT_VALUE",
        "input": "INSERT_INPUT_DATA",
        "nonce": "INSERT_NONCE"
    }],
    "id":1
}'
```

Ensure to replace the `INSERT_SENDER_ADDRESS`, `INSERT_RECIPIENT_ADDRESS`, `INSERT_GAS_LIMIT`, `INSERT_GAS_PRICE`, `INSERT_VALUE`, `INSERT_INPUT_DATA`, and `INSERT_NONCE` with the proper values.

---

### eth_syncing

Returns an object with syncing data or `false` if not syncing. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#eth_syncing).

**Parameters**:

None.

**Example**:

```bash title="eth_syncing"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"eth_syncing",
    "params":[],
    "id":1
}'
```

---

### net_listening

Returns `true` if the client is actively listening for network connections, otherwise `false`. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#net_listening).

**Parameters**:

None.

**Example**:

```bash title="net_listening"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"net_listening",
    "params":[],
    "id":1
}'
```

---

### net_peerCount

Returns the number of peers connected to the client.

**Parameters**:

None.

**Example**:

```bash title="net_peerCount"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"net_peerCount",
    "params":[],
    "id":1
}'
```

---

### net_version

Returns the current network ID as a string. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#net_version).

**Parameters**:

None.

**Example**:

```bash title="net_version"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"net_version",
    "params":[],
    "id":1
}'
```

---

### system_health

Returns information about the health of the system.

**Parameters**:

None.

**Example**:

```bash title="system_health"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"system_health",
    "params":[],
    "id":1
}'
```

---

### web3_clientVersion

Returns the current client version. [Reference](https://ethereum.org/developers/docs/apis/json-rpc/#web3_clientversion).

**Parameters**:

None.

**Example**:

```bash title="web3_clientVersion"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"web3_clientVersion",
    "params":[],
    "id":1
}'
```

---

### debug_traceBlockByNumber 

Traces a block's execution by its number and returns a detailed execution trace for each transaction.

**Parameters**:

- **`blockValue` ++"string"++**: The block number or tag to trace. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).
- **`options` ++"object"++**: (Optional) An object containing tracer options.
    - **`tracer` ++"string"++**: The name of the tracer to use (e.g., `"callTracer"`, `"opTracer"`).
    - Other tracer-specific options may be supported.

**Example**:

```bash title="debug_traceBlockByNumber"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"debug_traceBlockByNumber",
    "params":["INSERT_BLOCK_VALUE", {"tracer": "callTracer"}],
    "id":1
}'
```

Ensure to replace `INSERT_BLOCK_VALUE` with a proper block number if needed.

---

### debug_traceTransaction

Traces the execution of a single transaction by its hash and returns a detailed execution trace.

**Parameters**:

- **`transactionHash` ++"string"++**: The hash of the transaction to trace. Must be a [32 byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
- **`options` ++"object"++**: (Optional) An object containing tracer options (e.g., `tracer: "callTracer"`).

**Example**:

```bash title="debug_traceTransaction"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"debug_traceTransaction",
    "params":["INSERT_TRANSACTION_HASH", {"tracer": "callTracer"}],
    "id":1
}'
```

Ensure to replace the `INSERT_TRANSACTION_HASH` with the proper value.

!!! note "Differences from Ethereum (Geth)"
    When using the default struct logger (opcode tracer), there is a difference in how `gasCost` is calculated for CALL-like opcodes (`CALL`, `DELEGATECALL`, `STATICCALL`, `CREATE`, `CREATE2`):

    - **Geth behavior**: The `gasCost` includes the opcode's intrinsic cost plus all gas forwarded to child calls.
    - **Polkadot Hub behavior**: The `gasCost` includes only the opcode's intrinsic cost, excluding forwarded gas. The intrinsic cost covers:
        - Base cost of the CALL opcode.
        - Post-call costs (for example, copying return data back to the caller's memory).

---

### debug_traceCall

Executes a new message call and returns a detailed execution trace without creating a transaction on the blockchain.

**Parameters**:

- **`transaction` ++"object"++**: The transaction call object, similar to `eth_call` parameters.
    - **`to` ++"string"++**: Recipient address of the call. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`data` ++"string"++**: Hash of the method signature and encoded parameters. Must be a [data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`from` ++"string"++**: (Optional) Sender's address for the call. Must be a [20-byte data](https://ethereum.org/developers/docs/apis/json-rpc/#unformatted-data-encoding) string.
    - **`gas` ++"string"++**: (Optional) Gas limit to execute the call. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`gasPrice` ++"string"++**: (Optional) Gas price per unit of gas. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
    - **`value` ++"string"++**: (Optional) Value in wei to send with the call. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string.
- **`blockValue` ++"string"++**: (Optional) Block tag or block number to execute the call at. Must be a [quantity](https://ethereum.org/developers/docs/apis/json-rpc/#quantities-encoding) string or a [default block parameter](https://ethereum.org/developers/docs/apis/json-rpc/#default-block).
- **`options` ++"object"++**: (Optional) An object containing tracer options (e.g., `tracer: "callTracer"`).

**Example**:

```bash title="debug_traceCall"
curl -X POST https://services.polkadothub-rpc.com/testnet \
-H "Content-Type: application/json" \
--data '{
    "jsonrpc":"2.0",
    "method":"debug_traceCall",
    "params":[{
        "from": "INSERT_SENDER_ADDRESS",
        "to": "INSERT_RECIPIENT_ADDRESS",
        "data": "INSERT_ENCODED_CALL"
    }, "INSERT_BLOCK_VALUE", {"tracer": "callTracer"}],
    "id":1
}'
```

Ensure to replace the `INSERT_SENDER_ADDRESS`, `INSERT_RECIPIENT_ADDRESS`, `INSERT_ENCODED_CALL`, and `INSERT_BLOCK_VALUE` with the proper value.

---

## Response Format

All responses follow the standard JSON-RPC 2.0 format:

```json
{
    "jsonrpc": "2.0",
    "id": 1,
    "result": ... // The return value varies by method
}
```

## Error Handling

If an error occurs, the response will include an error object:

```json
{
    "jsonrpc": "2.0",
    "id": 1,
    "error": {
        "code": -32000,
        "message": "Error message here"
    }
}
```