Estimate Transaction Fees and Priority Fees

Estimate Transaction Fees and Priority Fees

Price a transaction message and sample the priority fee market.

1. Fetch a recent blockhash and the last block height at which it remains valid. The fee quote is only meaningful while this blockhash lives.
2. Ask the cluster what base fee it would charge for the supplied message. A null value means the blockhash inside the message has already expired.
3. Sample the prioritization fees recently paid by transactions touching the same write-locked accounts, so a competitive compute-unit price can be set rather than guessed.
4. Confirm the blockhash fetched at the start has not expired while the fees were being sampled. If it has, the caller must restart with a fresh blockhash before signing.

What you'll need to have ready

• encodedMessage: The base64-encoded transaction message (not a full signed transaction) to be priced.
• writableAccounts: Base58-encoded account addresses the transaction will write-lock, used to sample the relevant priority fee market.

For your developer

Arazzo workflow solana:fee-estimation, 4 operations: getLatestBlockhash → getFeeForMessage → getRecentPrioritizationFees → isBlockhashValid. Specs on APIs.io.