# Transaction errors explained

> Blockchain transaction errors, each with the exact messages clients print and how to fix it.

Source: https://hashspan.dev/errors

- [Execution reverted: what it means and how to fix it](https://hashspan.dev/errors/execution-reverted.md): Execution reverted means the contract code stopped on purpose. See the two ways you meet it, how to read the reason, and how it looks in a trace.
- [Insufficient funds for gas * price + value: cause and fix](https://hashspan.dev/errors/insufficient-funds.md): Insufficient funds means the sender cannot pay the gas limit times the max fee, plus the value. See what the node checks, why it fires, and how to fix it.
- [Intrinsic gas too low: cause and fix](https://hashspan.dev/errors/intrinsic-gas-too-low.md): The gas limit is below the minimum a transaction needs to start. See what intrinsic gas is, why a hardcoded limit causes it, and how it differs from out of gas.
- [Max fee per gas less than block base fee: cause and fix](https://hashspan.dev/errors/max-fee-per-gas-less-than-block-base-fee.md): The fee cap you set is below the block's base fee, so the node refuses it. See what the cap must clear, why hardcoded fees and unit slips cause it, and the fix.
- [Nonce too low in Ethereum: cause and fix](https://hashspan.dev/errors/nonce-too-low.md): Nonce too low means the account already used that nonce. See where the node refuses it, why retries and parallel workers cause it, and how to fix it.
- [Out of gas in Ethereum: cause and fix](https://hashspan.dev/errors/out-of-gas.md): A transaction that runs out of gas is mined, reverted and still paid. See why the gas limit is the cause, how to spot it, and how to fix it.
- [Replacement transaction underpriced: cause and fix](https://hashspan.dev/errors/replacement-transaction-underpriced.md): A second transaction with the same nonce must pay more than the first. See why the node refuses it, how much more, and how to speed up or cancel.
- [Transaction dropped and replaced: meaning and fix](https://hashspan.dev/errors/transaction-dropped-and-replaced.md): Etherscan shows Dropped & Replaced when another transaction with the same nonce was mined. Who replaced it, was the fee paid, and what to do next.
- [Transaction stuck pending: causes and fix](https://hashspan.dev/errors/transaction-stuck-pending.md): A transaction with a hash but no receipt is waiting in the mempool. Find out if it is a nonce gap or a fee below the base fee, and how to unstick it.