Pre-Sign Slippage Impact Explainer

WHAT IT DOES

Pre-Sign Slippage Impact Explainer reads pending swap transaction data from your wallet or a transaction hash, extracts the estimated output amount and minimum output (slippage tolerance) from the swap function call, and calculates the slippage percentage. It analyzes the risk of the transaction failing due to slippage, classifies the risk level (safe, moderate, or high), and generates an AI explanation of what slippage means for this transaction and whether the tolerance is reasonable.

HOW TO USE

When your wallet prompts you to sign a swap transaction, copy the transaction hash from your wallet or the requesting dApp. Open the Pre-Sign Slippage Impact Explainer, connect your EVM wallet, and paste the transaction hash into the input field. Click "Look up transaction" to fetch the swap details and generate a slippage analysis. Alternatively, click "Manual entry" to enter the estimated output, minimum output, value, and gas limit directly. The tool will display the estimated output, minimum output, slippage percentage, risk level, and a plain-language explanation. Review the AI explanation to understand whether your slippage tolerance is appropriate for current market conditions.

TECHNICAL SECTION — SWAP SLIPPAGE ANALYSIS

The tool fetches transaction data from the blockchain using the connected wallet's provider, extracting the value, gas limit, and data payload. It attempts to decode common swap function signatures including swapExactTokensForTokens (0x38ed1739) and swapExactETHForTokens (0x5ae401dc) to extract the estimated output and minimum output amounts from the calldata. The tool then calculates the slippage percentage using the formula: ((estimated - minimum) / estimated) * 100. A slippage tolerance above 10% is flagged as high risk, above 3% as moderate risk, and below 3% as low risk. The AI layer receives the decoded data and current network context, generating a plain-language explanation of the slippage impact and advising on whether the tolerance is reasonable for the current market conditions. This approach helps you understand the risk of your swap failing before you sign.

WHAT IT CANNOT SEE

This tool cannot predict actual slippage that will occur at the time of execution. It cannot account for network latency between simulation and execution. It cannot detect if the pool will be manipulated by other transactions before the swap is mined. It cannot read private mempool data. It cannot guarantee that the minimum output amount will be sufficient to cover slippage. The user must still verify the transaction details and slippage settings in their wallet before signing. The AI explanation is generated from on-chain data and does not constitute financial advice.

PLEASE NOTE

EVM chains only. Explanations are AI-generated from data the app reads on-chain—always review what you are actually signing in your wallet before approving it. The wallet's own signature prompt remains the final and only protection against unwanted transactions. This tool is read-only; it never sends transactions or signs anything on your behalf.