Nonce Gap Filler

WHAT IT DOES

Nonce Gap Filler is a wallet-focused tool that detects and fills gaps in a wallet's nonce sequence, restoring the ability to submit new transactions. When a transaction gets stuck with a low nonce, all subsequent transactions with higher nonces are blocked because EVM chains require transactions to execute in strict nonce order. This tool identifies skipped nonces and fills them with zero-value self-transfer transactions, allowing the wallet to continue sending transactions normally. It reads the wallet's transaction count, identifies pending transaction nonces, checks the transaction pool state, analyzes the account nonce sequence, and calculates appropriate gas prices for filler transactions. The tool supports Ethereum, Polygon, Arbitrum, Optimism, Avalanche, BNB Chain, and Base, providing a unified interface to detect and resolve nonce gaps across multiple networks. This is essential for users who have had transactions stuck in the mempool and can no longer send new transactions.

HOW TO USE

Connect your wallet using WalletConnect or a compatible browser extension. Ensure your wallet is on the network where the nonce gap exists. Enter a gas price in gwei for the filler transactions—use a competitive gas price to ensure the filler transactions are mined quickly. Set a maximum nonce gap to detect (default 10). Click "Detect gaps" to scan your wallet's nonce sequence: the tool reads the current mined nonce, checks the pending transaction pool, and identifies any skipped nonces. The tool displays a visual grid showing your nonce sequence, highlighting gaps in amber. If gaps are detected, the "Fill gaps" button appears. Click it to submit zero-value self-transfer transactions for each gap, sequentially filling the gaps. The tool displays a transaction link to your chain's block explorer and logs the final gas cost for each filler transaction using receipt.effectiveGasPrice.

ADAPTIVE NONCE GAP DETECTION AND SEQUENTIAL FILL ENGINE

The core technical mechanism that distinguishes this tool is its adaptive nonce gap detection and sequential fill engine. Unlike manual transaction inspection, which requires users to check nonces individually, this tool automates gap detection and filling. The engine first reads the wallet's transaction count using eth_getTransactionCount with the 'latest' parameter to get the last mined nonce. It then reads the 'pending' transaction count to identify how many transactions are in the mempool. The engine calculates the gap range by comparing these values—any nonce between the latest mined nonce and the pending nonce range that is not already mined is considered a gap. The engine also performs a safety check by iterating through the gap range and verifying that each nonce is actually pending using a combination of eth_getTransactionByBlockHashAndIndex and mempool queries. Once gaps are identified, the engine submits filler transactions sequentially, waiting for each confirmation before submitting the next, ensuring nonce order is preserved. Each filler transaction is a 0 ETH self-transfer with a gas limit of 21000, using the user-specified gas price. All RPC calls are wrapped with timeout and retry logic, and the tool automatically falls back to a secondary provider if the primary endpoint fails or rate-limits, ensuring gap detection completes even during network congestion.

WHAT IT CANNOT SEE

The tool cannot guarantee that nonce gaps will be filled correctly if the network is congested, the wallet submits new transactions during the filling process, the estimated gas prices are insufficient for the filler transactions to be mined, or the original stuck transactions are mined before the filler transactions are confirmed. It has no visibility into the exact mempool state across all nodes, nor can it predict how quickly miners will process the filler transactions. The tool cannot detect if a new gap forms during the filling process. It does not monitor the wallet for new transactions after filling—it is a gap filler, not a continuous monitoring service. The tool cannot interact with non-EVM chains, private networks, or wallets that do not support standard transaction nonce handling.

PLEASE NOTE

This tool is designed exclusively for EVM-compatible blockchain networks. It supports Ethereum, Polygon, Arbitrum, Optimism, Avalanche, BNB Chain, Base, and similar chains. Non-EVM networks such as Solana, Cosmos, or Bitcoin are not supported. Always verify the gas price and gap detection before filling—the tool does not validate wallet safety beyond basic nonce verification. The tool provides estimates only—actual fees and gas costs are determined at the time of transaction execution. Users are responsible for understanding the risks of filling nonce gaps, including the possibility that filler transactions may increase gas costs.