Submit Transactions

Submit a signed transaction to Solana through BlockSprint's optimized infrastructure.

Request

json

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "sendTransaction",
  "params": [
    "<base64_encoded_transaction>",
    {
      "encoding": "base64",
      "skipPreflight": true,
      "maxRetries": 0
    }
  ]
}

Parameters

Parameter	Type	Required	Default	Description
`transaction`	string	Yes	—	Base64 or Base58 encoded signed transaction
`encoding`	string	No	`"base64"`	`"base64"` or `"base58"`
`skipPreflight`	boolean	No	`true`	Skip preflight simulation (recommended: `true`)
`maxRetries`	number	No	`0`	RPC retries (recommended: `0`)

Response

json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "5VERv8NMvzbJMEkV8xnrLkEaWRtSz9CosKDYjCJjBRnbJLgp8uirBgmQpjKhoR4tjF3ZpRzrFmBV6UjKdiSZkQUW"
}

The result is the transaction signature (Base58 encoded). It means the transaction was accepted, not that it landed: check it with getSignatureStatuses on your Solana RPC, and re-send the same signed transaction every ~2 seconds until it confirms or its blockhash expires.

Errors

Errors are returned as a JSON-RPC error object.

HTTP	Code	Message	Cause
401	`-32600`	`Missing API key` / `Invalid API key`	No API key, or the key is unknown or disabled
403	`-32600`	`API key has expired` / `IP address not whitelisted`	The key has expired, or your IP is not on its allowlist
403	`-32601`	`Method '…' is not allowed for this API key`	The key is restricted to other methods
400	`-32700`	`Parse error`	The body is not valid JSON-RPC 2.0
400	`-32602`	`Missing transaction parameter` / `Invalid transaction format` / `Invalid base64 encoding`	The transaction is missing or could not be decoded
400	`-32602`	`No tip transfer found. …`	No tip transfer to a BlockSprint tip address
400	`-32602`	`Tip amount too low: …`	The tip is below the minimum of 0.001 SOL
400	`-32602`	`Invalid tip wallet: …`	The tip transfer is not valid
501	`-32601`	`Method not implemented …`	Any method other than `sendTransaction` and `getHealth`

Endpoint

POST https://global.blocksprint.io/api/v1/YOUR_API_KEY

Or:

POST https://global.blocksprint.io/

With X-API-Key header or ?api_key= query parameter.

BlockSprint endpoints serve sendTransaction and getHealth. Use your Solana RPC for other methods, such as getLatestBlockhash and getSignatureStatuses.

URI Parameters

Constraint	Type	Default	Description
mevProtect	bool	false	Enables MEV protection
swqosOnly	bool	false	Only uses SWQOS

Transaction Requirements

Must be signed

Include all required signatures.

Must include tip

Transfer 0.001+ SOL to a BlockSprint tip address.

Valid blockhash

Use a recent blockhash from your Solana RPC (expires in ~60-90 seconds).

Transaction V1

BlockSprint accepts legacy, v0 and Transaction V1 transactions. Send a V1 transaction like any other, base64-encoded; V1 transactions can be up to 4096 bytes.

INFO

Build V1 with an SDK version that supports it: @solana/kit 8.0.0, @solana/web3.js 3.0.0-rc.3, Rust solana-* crates 4.2, solders 0.29.0 or solana-go 1.23.0 (or later).
Set the compute-unit limit and the loaded-accounts data size limit explicitly: in V1 an unset limit is 0.
The V1 priority fee is a total in lamports, not micro-lamports per compute unit.
The tip is the same System Program transfer to a BlockSprint tip address.
To read a V1 transaction with getTransaction, pass maxSupportedTransactionVersion: 1.

Code Examples