Sei JSON-RPC API Reference

Sei's EVM layer provides full compatibility with Ethereum JSON-RPC specification, allowing you to use familiar Ethereum tools and libraries while benefiting from Sei's parallelized execution and sub-second finality.

Base URL

https://api.blockeden.xyz/sei/<your-api-key>

Standard EVM Methods

Account Methods

eth_getBalance

Get the balance of an account at a given block.

Parameters:

address (string) - 20-byte address to check for balance
blockNumber (string) - Block number in hex, or "latest", "earliest", "pending"

Returns: Balance in wei as a hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getBalance",
    "params": ["0x742D5Cc6bF2442E8C7c74c7b4Be6AB9d6f10f5B4", "latest"],
    "id": 1
  }'

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x1bc16d674ec80000"
}

eth_getTransactionCount

Get the number of transactions sent from an address (nonce).

Parameters:

address (string) - 20-byte address
blockNumber (string) - Block number in hex, or "latest", "earliest", "pending"

Returns: Transaction count as hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getTransactionCount",
    "params": ["0x742D5Cc6bF2442E8C7c74c7b4Be6AB9d6f10f5B4", "latest"],
    "id": 1
  }'

eth_getCode

Get the code at a given address.

Parameters:

address (string) - 20-byte address
blockNumber (string) - Block number in hex, or "latest", "earliest", "pending"

Returns: Code as hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getCode",
    "params": ["0xA0b86a33E6c0e4A2a2a5FB1C6A6D6a30BF8b6B3a", "latest"],
    "id": 1
  }'

Block Methods

eth_blockNumber

Get the current block number.

Parameters: None

Returns: Current block number as hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_blockNumber",
    "params": [],
    "id": 1
  }'

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x4b7"
}

eth_getBlockByNumber

Get block information by block number.

Parameters:

blockNumber (string) - Block number in hex, or "latest", "earliest", "pending"
fullTransactions (boolean) - If true, returns full transaction objects; if false, only hashes

Returns: Block object or null

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getBlockByNumber",
    "params": ["latest", true],
    "id": 1
  }'

eth_getBlockByHash

Get block information by block hash.

Parameters:

blockHash (string) - 32-byte block hash
fullTransactions (boolean) - If true, returns full transaction objects; if false, only hashes

Returns: Block object or null

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getBlockByHash",
    "params": ["0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef", false],
    "id": 1
  }'

Transaction Methods

eth_getTransactionByHash

Get transaction information by transaction hash.

Parameters:

transactionHash (string) - 32-byte transaction hash

Returns: Transaction object or null

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getTransactionByHash",
    "params": ["0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef"],
    "id": 1
  }'

eth_getTransactionReceipt

Get transaction receipt by transaction hash.

Parameters:

transactionHash (string) - 32-byte transaction hash

Returns: Transaction receipt object or null

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getTransactionReceipt",
    "params": ["0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef"],
    "id": 1
  }'

Response Example:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "blockHash": "0xb3b20624f8f0f86eb50dd04688409e5cea4bd02d700bf6e79e9384d47d6a5a35",
    "blockNumber": "0x5bad55",
    "contractAddress": null,
    "cumulativeGasUsed": "0xb90b0",
    "from": "0x398137383b3d25c92898c656696e41950e47316b",
    "gasUsed": "0x1383f",
    "logs": [],
    "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
    "status": "0x1",
    "to": "0x06012c8cf97bead5deae237070f9587f8e7a266d",
    "transactionHash": "0xc6ef2fc5426d6ad6fd9e2a26abeab0aa2411b7ab17f30a99d3cb96aed1d1055b",
    "transactionIndex": "0x41"
  }
}

eth_sendRawTransaction

Submit a signed transaction to the network.

Parameters:

signedTransaction (string) - Signed transaction data as hex string

Returns: Transaction hash

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_sendRawTransaction",
    "params": ["0xf86c808504a817c800825208943535353535353535353535353535353535353535880de0b6b3a76400008025a04f4c17305743700648bc4f6cd3038ec6f6af0df73e31757d8a17c7e9e1f3c7fd2a053a8ffdc8ab1f4b5a1e4d9b4a2c3a6b4a6e1e8c4b4d6c6d6e1b4a6e1e8c4b4"],
    "id": 1
  }'

Smart Contract Interaction

eth_call

Execute a smart contract function call without creating a transaction.

Parameters:

callObject (object) - Call parameters
- to (string) - Contract address
- data (string) - Encoded function call data
- from (string, optional) - Sender address
- gas (string, optional) - Gas limit
- gasPrice (string, optional) - Gas price
- value (string, optional) - Value to send
blockNumber (string) - Block number in hex, or "latest", "earliest", "pending"

Returns: Return value of the call

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_call",
    "params": [
      {
        "to": "0xA0b86a33E6c0e4A2a2a5FB1C6A6D6a30BF8b6B3a",
        "data": "0x70a08231000000000000000000000000742D5Cc6bF2442E8C7c74c7b4Be6AB9d6f10f5B4"
      },
      "latest"
    ],
    "id": 1
  }'

eth_estimateGas

Estimate gas needed for a transaction.

Parameters:

transactionObject (object) - Transaction parameters
- to (string, optional) - Recipient address
- from (string, optional) - Sender address
- data (string, optional) - Transaction data
- value (string, optional) - Value to send
- gas (string, optional) - Gas limit
- gasPrice (string, optional) - Gas price

Returns: Estimated gas amount as hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_estimateGas",
    "params": [
      {
        "to": "0x742D5Cc6bF2442E8C7c74c7b4Be6AB9d6f10f5B4",
        "value": "0xde0b6b3a7640000"
      }
    ],
    "id": 1
  }'

Gas and Fee Methods

eth_gasPrice

Get current gas price.

Parameters: None

Returns: Current gas price in wei as hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_gasPrice",
    "params": [],
    "id": 1
  }'

eth_feeHistory

Get fee history for a range of blocks (EIP-1559).

Parameters:

blockCount (string) - Number of blocks to return fee history for
newestBlock (string) - Block number in hex, or "latest", "earliest", "pending"
rewardPercentiles (array) - Array of percentiles to return (0-100)

Returns: Fee history object

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_feeHistory",
    "params": ["10", "latest", [25, 50, 75]],
    "id": 1
  }'

eth_maxPriorityFeePerGas

Get suggested max priority fee per gas for EIP-1559 transactions.

Parameters: None

Returns: Suggested max priority fee per gas as hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_maxPriorityFeePerGas",
    "params": [],
    "id": 1
  }'

Event and Log Methods

eth_getLogs

Get logs matching a filter.

Parameters:

filterObject (object) - Filter parameters
- fromBlock (string, optional) - Starting block
- toBlock (string, optional) - Ending block
- address (string|array, optional) - Contract address(es)
- topics (array, optional) - Array of topic filters
- blockHash (string, optional) - Block hash (cannot be used with fromBlock/toBlock)

Returns: Array of log objects

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getLogs",
    "params": [
      {
        "fromBlock": "0x1",
        "toBlock": "latest",
        "address": "0xA0b86a33E6c0e4A2a2a5FB1C6A6D6a30BF8b6B3a",
        "topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]
      }
    ],
    "id": 1
  }'

Response Example:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    {
      "address": "0xa0b86a33e6c0e4a2a2a5fb1c6a6d6a30bf8b6b3a",
      "topics": [
        "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
        "0x000000000000000000000000742d5cc6bf2442e8c7c74c7b4be6ab9d6f10f5b4",
        "0x000000000000000000000000a0b86a33e6c0e4a2a2a5fb1c6a6d6a30bf8b6b3a"
      ],
      "data": "0x0000000000000000000000000000000000000000000000000de0b6b3a7640000",
      "blockNumber": "0x4b7",
      "transactionHash": "0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef",
      "transactionIndex": "0x0",
      "blockHash": "0xabcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890",
      "logIndex": "0x0",
      "removed": false
    }
  ]
}

Network Information

eth_chainId

Get the chain ID of the current network.

Parameters: None

Returns: Chain ID as hex string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_chainId",
    "params": [],
    "id": 1
  }'

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x531"
}

net_version

Get the network ID.

Parameters: None

Returns: Network ID as string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "net_version",
    "params": [],
    "id": 1
  }'

web3_clientVersion

Get the client version.

Parameters: None

Returns: Client version string

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "web3_clientVersion",
    "params": [],
    "id": 1
  }'

Sei-Specific Features

Parallelized Execution

Sei's EVM supports optimistic parallelization, meaning independent transactions can execute in parallel for better performance:

# These transactions may execute in parallel if they don't conflict
curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '[
    {
      "jsonrpc": "2.0",
      "method": "eth_sendRawTransaction",
      "params": ["0x...tx1..."],
      "id": 1
    },
    {
      "jsonrpc": "2.0",
      "method": "eth_sendRawTransaction",
      "params": ["0x...tx2..."],
      "id": 2
    }
  ]'

Sub-Second Finality

Transactions on Sei typically confirm in ~400ms:

// Transaction confirmation is much faster than Ethereum
const txResponse = await provider.sendTransaction(tx);
const receipt = await txResponse.wait(); // Usually completes in <1 second

Batch Requests

You can send multiple RPC calls in a single HTTP request:

curl -X POST https://api.blockeden.xyz/sei/<your-api-key> \
  -H "Content-Type: application/json" \
  -d '[
    {
      "jsonrpc": "2.0",
      "method": "eth_blockNumber",
      "params": [],
      "id": 1
    },
    {
      "jsonrpc": "2.0",
      "method": "eth_gasPrice",
      "params": [],
      "id": 2
    },
    {
      "jsonrpc": "2.0",
      "method": "eth_getBalance",
      "params": ["0x742D5Cc6bF2442E8C7c74c7b4Be6AB9d6f10f5B4", "latest"],
      "id": 3
    }
  ]'

Error Handling

Standard JSON-RPC Error Codes

Code	Message	Description
-32700	Parse error	Invalid JSON
-32600	Invalid Request	JSON-RPC request is invalid
-32601	Method not found	Method does not exist
-32602	Invalid params	Invalid method parameters
-32603	Internal error	Internal JSON-RPC error

Sei-Specific Error Codes

Code	Message	Description
-32000	Transaction reverted	Smart contract execution failed
-32001	Insufficient funds	Account balance too low
-32002	Nonce too low	Transaction nonce already used
-32003	Gas limit exceeded	Transaction ran out of gas

Example Error Response

{
  "jsonrpc": "2.0",
  "error": {
    "code": -32602,
    "message": "Invalid params",
    "data": "Invalid address format"
  },
  "id": 1
}

Rate Limits

BlockEden.xyz implements fair usage policies:

Free Tier: 100 requests/second
Pro Tier: 1,000 requests/second
Enterprise: Custom limits

Rate limit headers in responses:

X-RateLimit-Limit: 100
X-RateLimit-Remaining: 99
X-RateLimit-Reset: 1640995200

Network Configuration

Mainnet (Pacific-1)

Chain ID: 1329
Currency Symbol: SEI
Currency Decimals: 18
RPC URL: https://api.blockeden.xyz/sei/<your-api-key>
Explorer: https://seitrace.com

WebSocket Subscriptions

Real-time event subscriptions are available via WebSocket:

const ws = new WebSocket('wss://api.blockeden.xyz/sei/<your-api-key>');

// Subscribe to new blocks
ws.send(JSON.stringify({
  jsonrpc: '2.0',
  method: 'eth_subscribe',
  params: ['newHeads'],
  id: 1
}));

// Subscribe to pending transactions
ws.send(JSON.stringify({
  jsonrpc: '2.0',
  method: 'eth_subscribe',
  params: ['newPendingTransactions'],
  id: 2
}));

// Subscribe to contract events
ws.send(JSON.stringify({
  jsonrpc: '2.0',
  method: 'eth_subscribe',
  params: ['logs', {
    address: '0xA0b86a33E6c0e4A2a2a5FB1C6A6D6a30BF8b6B3a',
    topics: ['0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef']
  }],
  id: 3
}));

Performance Tips

1. Use Batch Requests

Combine multiple calls to reduce latency:

const batch = [
  { jsonrpc: '2.0', method: 'eth_blockNumber', params: [], id: 1 },
  { jsonrpc: '2.0', method: 'eth_gasPrice', params: [], id: 2 }
];

2. Leverage Sei's Speed

Take advantage of sub-second finality for better UX:

// No need for long confirmation waits
const receipt = await txResponse.wait(1); // Usually completes quickly

3. Use WebSockets for Real-time Data

Avoid polling by using WebSocket subscriptions for live updates.

Next Steps

Learn about Sei Cosmos REST API for native Cosmos functionality
Check out Sei WebSocket Guide for real-time data streaming
Visit BlockEden.xyz Dashboard to monitor your API usage

Resources

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Base URL​

Standard EVM Methods​

Account Methods​

eth_getBalance​

eth_getTransactionCount​

eth_getCode​

Block Methods​

eth_blockNumber​

eth_getBlockByNumber​

eth_getBlockByHash​

Transaction Methods​

eth_getTransactionByHash​

eth_getTransactionReceipt​

eth_sendRawTransaction​

Smart Contract Interaction​

eth_call​

eth_estimateGas​

Gas and Fee Methods​

eth_gasPrice​

eth_feeHistory​

eth_maxPriorityFeePerGas​

Event and Log Methods​

eth_getLogs​

Network Information​

eth_chainId​

net_version​

web3_clientVersion​

Sei-Specific Features​

Parallelized Execution​

Sub-Second Finality​

Batch Requests​

Error Handling​

Standard JSON-RPC Error Codes​

Sei-Specific Error Codes​

Example Error Response​

Rate Limits​

Network Configuration​

Mainnet (Pacific-1)​

WebSocket Subscriptions​

Performance Tips​

1. Use Batch Requests​

2. Leverage Sei's Speed​

3. Use WebSockets for Real-time Data​

Next Steps​

Resources​

Base URL

Standard EVM Methods

Account Methods

eth_getBalance

eth_getTransactionCount

eth_getCode

Block Methods

eth_blockNumber

eth_getBlockByNumber

eth_getBlockByHash

Transaction Methods

eth_getTransactionByHash

eth_getTransactionReceipt

eth_sendRawTransaction

Smart Contract Interaction

eth_call

eth_estimateGas

Gas and Fee Methods

eth_gasPrice

eth_feeHistory

eth_maxPriorityFeePerGas

Event and Log Methods

eth_getLogs

Network Information

eth_chainId

net_version

web3_clientVersion

Sei-Specific Features

Parallelized Execution

Sub-Second Finality

Batch Requests

Error Handling

Standard JSON-RPC Error Codes

Sei-Specific Error Codes

Example Error Response

Rate Limits

Network Configuration

Mainnet (Pacific-1)

WebSocket Subscriptions

Performance Tips

1. Use Batch Requests

2. Leverage Sei's Speed

3. Use WebSockets for Real-time Data

Next Steps

Resources