> ## Documentation Index
> Fetch the complete documentation index at: https://voltaire.tevm.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# Transaction.getGasPrice

> Get effective gas price for transaction

<Card title="Try it Live" icon="play" href="https://playground.tevm.sh?example=primitives/transaction.ts">
  Run Transaction examples in the interactive playground
</Card>

# getGasPrice

Get effective gas price for transaction.

<Tabs />

## Gas Price Calculation

### Legacy & EIP-2930 Transactions

Fixed gas price model:

```typescript theme={null}
getGasPrice(tx) = tx.gasPrice
```

Simple and predictable - users specify exact gas price willing to pay.

### EIP-1559, EIP-4844, EIP-7702 Transactions

Dynamic fee market:

```typescript theme={null}
effectiveGasPrice = min(
  maxFeePerGas,
  baseFee + maxPriorityFeePerGas
)
```

**Components:**

* `baseFee` - Current network base fee (burned)
* `maxPriorityFeePerGas` - Maximum tip to miner
* `maxFeePerGas` - Maximum total willing to pay

**Examples:**

```typescript theme={null}
// Scenario 1: Normal conditions
baseFee = 15 gwei
maxPriorityFeePerGas = 2 gwei
maxFeePerGas = 30 gwei

effectiveGasPrice = min(30, 15 + 2) = 17 gwei

// Scenario 2: High congestion
baseFee = 100 gwei
maxPriorityFeePerGas = 2 gwei
maxFeePerGas = 30 gwei

effectiveGasPrice = min(30, 100 + 2) = 30 gwei  // Capped at maxFee

// Scenario 3: Priority fee adjustment
baseFee = 20 gwei
maxPriorityFeePerGas = 15 gwei
maxFeePerGas = 50 gwei

effectiveGasPrice = min(50, 20 + 15) = 35 gwei
```

## Usage Patterns

### Transaction Cost Estimation

```typescript theme={null}
import { getGasPrice } from 'tevm/Transaction'

async function estimateTransactionCost(
  tx: Transaction.Any,
  baseFee?: bigint
): Promise<bigint> {
  const gasPrice = getGasPrice(tx, baseFee)
  const gasLimit = tx.gasLimit

  return gasPrice * gasLimit + tx.value
}

// Usage
const cost = await estimateTransactionCost(tx, currentBaseFee)
console.log(`Estimated cost: ${cost} wei`)
```

### Gas Price Comparison

```typescript theme={null}
import { getGasPrice } from 'tevm/Transaction'

function compareGasPrices(
  tx1: Transaction.Any,
  tx2: Transaction.Any,
  baseFee: bigint
): number {
  const price1 = getGasPrice(tx1, baseFee)
  const price2 = getGasPrice(tx2, baseFee)

  if (price1 < price2) return -1
  if (price1 > price2) return 1
  return 0
}

// Sort transactions by gas price
const sorted = transactions.sort((a, b) =>
  compareGasPrices(a, b, currentBaseFee)
)
```

### Balance Validation

```typescript theme={null}
import { getGasPrice } from 'tevm/Transaction'

async function validateBalance(
  tx: Transaction.Any,
  senderAddress: AddressType,
  baseFee: bigint
): Promise<boolean> {
  const balance = await getBalance(senderAddress)
  const gasPrice = getGasPrice(tx, baseFee)
  const totalCost = gasPrice * tx.gasLimit + tx.value

  return balance >= totalCost
}
```

### Transaction Pool Sorting

```typescript theme={null}
import { getGasPrice } from 'tevm/Transaction'

class TransactionPool {
  sortByGasPrice(baseFee: bigint): Transaction.Any[] {
    return this.transactions.sort((a, b) => {
      const priceA = getGasPrice(a, baseFee)
      const priceB = getGasPrice(b, baseFee)
      return Number(priceB - priceA)  // Descending order
    })
  }
}
```

## EIP-1559 Gas Price Components

```typescript theme={null}
import { getGasPrice } from 'tevm/Transaction'

function getGasPriceBreakdown(
  tx: Transaction.EIP1559,
  baseFee: bigint
) {
  const effectiveGasPrice = getGasPrice(tx, baseFee)
  const effectivePriorityFee = effectiveGasPrice - baseFee

  return {
    baseFee,
    priorityFee: effectivePriorityFee,
    totalGasPrice: effectiveGasPrice,
    maxFeePerGas: tx.maxFeePerGas,
    maxPriorityFeePerGas: tx.maxPriorityFeePerGas,
    refund: tx.maxFeePerGas - effectiveGasPrice  // Amount refunded
  }
}

// Usage
const breakdown = getGasPriceBreakdown(tx, baseFee)
console.log(`Paying: ${breakdown.totalGasPrice} wei/gas`)
console.log(`Refund: ${breakdown.refund} wei/gas`)
```

## See Also

* [getChainId](/primitives/transaction/get-chain-id) - Extract chain ID from transaction
* [format](/primitives/transaction/format) - Format transaction for display
* [FeeMarket](/primitives/feemarket) - Base fee and priority fee calculations
* [GasConstants](/primitives/gasconstants) - Gas cost constants

## References

* [EIP-1559: Fee market change for ETH 1.0 chain](https://eips.ethereum.org/EIPS/eip-1559)
* [EIP-2930: Optional access lists](https://eips.ethereum.org/EIPS/eip-2930)
* [Yellow Paper: Transaction Gas](https://ethereum.github.io/yellowpaper/paper.pdf)