BSC Gas Balance Tracker: Gas Bought, Refunded and Collected on BNB Chain

BNB Chain reports gas the way Ethereum does, in three balance changes per transaction: the sender's BNB drops by the gas limit times the gas price before execution, reason code 6; whatever gas was not used comes back after execution, reason code 7; and the fee for the gas that was used is credited to the block producer, reason code 5. The TransactionBalances cube records all three with the balance before and after, so the gas an address paid is the code 6 debit minus the code 7 refund, transaction by transaction. Every example runs in the IDE on a free account; the cube holds the recent realtime window only. The example address is a bot that sends transactions every few seconds, 0x10168749958f03a7c95432bd934058c77be787b0; swap in any sender.

Gas bought per transaction for one address

Code 6 rows for the sender over the last hour; the time window keeps the scan small on a chain this busy. gasBought is the balance before minus the balance after, which equals Gas times GasPrice on the transaction. calculate only sees fields that are selected, so keep both balances in the query. Saved query here.

{
  EVM(network: bsc) {
    TransactionBalances(
      where: {
        TokenBalance: {
          BalanceChangeReasonCode: { eq: 6 }
          Address: { is: "0x10168749958f03a7c95432bd934058c77be787b0" }
        }
        Block: { Time: { since_relative: { hours_ago: 1 } } }
      }
      limit: { count: 20 }
      orderBy: { descending: Block_Time }
    ) {
      Block {
        Time
        Number
      }
      TokenBalance {
        PreBalance
        PostBalance
        PostBalanceInUSD
      }
      Transaction {
        Hash
        Gas
        GasPrice
      }
      gasBought: calculate(
        expression: "$TokenBalance_PreBalance - $TokenBalance_PostBalance"
      )
    }
  }
}

Gas refunded to the same address

Code 7 rows are the unused gas coming back; a transaction that used its whole gas limit has none. Subtract this from the code 6 debit of the same hash to get the gas the transaction really cost. Saved query here.

{
  EVM(network: bsc) {
    TransactionBalances(
      where: {
        TokenBalance: {
          BalanceChangeReasonCode: { eq: 7 }
          Address: { is: "0x10168749958f03a7c95432bd934058c77be787b0" }
        }
        Block: { Time: { since_relative: { hours_ago: 1 } } }
      }
      limit: { count: 20 }
      orderBy: { descending: Block_Time }
    ) {
      Block {
        Time
      }
      TokenBalance {
        PreBalance
        PostBalance
      }
      Transaction {
        Hash
      }
      refund: calculate(
        expression: "$TokenBalance_PostBalance - $TokenBalance_PreBalance"
      )
    }
  }
}

The busiest gas payers right now

Group code 6 rows by address over a short window and count them. The top of the list is bots and exchange hot wallets. Saved query here.

{
  EVM(network: bsc) {
    TransactionBalances(
      where: {
        TokenBalance: { BalanceChangeReasonCode: { eq: 6 } }
        Block: { Time: { since_relative: { minutes_ago: 10 } } }
      }
      orderBy: { descendingByField: "transactions" }
      limit: { count: 20 }
    ) {
      TokenBalance {
        Address
      }
      transactions: count
    }
  }
}

Several addresses at once

in takes a list, and limitBy on the address keeps the newest row per address, so one query returns the latest gas debit of every wallet you watch. Saved query here.

{
  EVM(network: bsc) {
    TransactionBalances(
      where: {
        TokenBalance: {
          BalanceChangeReasonCode: { eq: 6 }
          Address: {
            in: [
              "0x10168749958f03a7c95432bd934058c77be787b0"
              "0x42d73da3daca18374ee1ab8d700351350a3b0064"
            ]
          }
        }
        Block: { Time: { since_relative: { hours_ago: 1 } } }
      }
      limitBy: { by: TokenBalance_Address, count: 1 }
      orderBy: { descending: Block_Time }
    ) {
      Block {
        Time
      }
      TokenBalance {
        Address
        PreBalance
        PostBalance
      }
      Transaction {
        Hash
        Gas
        GasPrice
      }
      gasBought: calculate(
        expression: "$TokenBalance_PreBalance - $TokenBalance_PostBalance"
      )
    }
  }
}

Stream the gas one address pays

The code 6 filter as a subscription delivers a message for every transaction the address sends, as it is indexed. Saved stream here.

subscription {
  EVM(network: bsc) {
    TransactionBalances(
      where: {
        TokenBalance: {
          BalanceChangeReasonCode: { eq: 6 }
          Address: { is: "0x10168749958f03a7c95432bd934058c77be787b0" }
        }
      }
    ) {
      Block {
        Time
      }
      TokenBalance {
        PreBalance
        PostBalance
      }
      Transaction {
        Hash
        GasPrice
      }
      gasBought: calculate(
        expression: "$TokenBalance_PreBalance - $TokenBalance_PostBalance"
      )
    }
  }
}

Where the fees go

The fee for used gas is credited with reason code 5 to BNB Chain's fee holder, 0xfffffffffffffffffffffffffffffffffffffffe, and moved to the ValidatorSet contract at the end of each block. The BSC MEV balance tracker streams those credits and shows fee income per block and per validator.

Frequently Asked Questions

How do I get the gas an address paid on BNB Chain?

Take its reason code 6 rows: PreBalance minus PostBalance is the gas bought for that transaction. Subtract the code 7 refund of the same hash for the amount finally spent.

Why are there two balance changes for gas in one transaction?

The gas limit is charged before execution (code 6) and the unused part is returned after it (code 7). The difference is the gas actually used times the gas price.

Can I see who pays the most gas on BSC?

Group reason code 6 rows by TokenBalance.Address over a window and count. Sorting by count gives the busiest senders; bots and exchange wallets lead.

Does Base use the same codes?

No. Base folds gas into the sender's code 0 balance change and credits fees to its fee vaults with code 5; see the Base gas balance tracker.

How far back does this data go?

TransactionBalances holds the recent realtime window only. For older gas costs use the Transactions cube, which carries gas and cost per transaction on the archive dataset.

Related pages

• BSC transaction balance tracker
• BSC MEV balance tracker
• Base gas balance tracker
• Balance change reason codes