{"id":72702,"date":"2026-09-18T22:55:01","date_gmt":"2026-09-18T19:55:01","guid":{"rendered":"https:\/\/lwallet.com.ua\/?p=72702"},"modified":"2026-09-18T22:55:01","modified_gmt":"2026-09-18T19:55:01","slug":"metamask-transaction-simulation","status":"publish","type":"post","link":"https:\/\/lwallet.com.ua\/en\/metamask-transaction-simulation\/","title":{"rendered":"Can you trust a transaction simulation in MetaMask?"},"content":{"rendered":"\r\n\r\n\r\n

When a dapp \u2014 a website or app connected to your wallet \u2014 sends a request to MetaMask, the wallet opens a confirmation screen. A MetaMask transaction simulation<\/strong> can show you, before you sign, how the transaction is expected to change your balance: for example, \u201c+1,240 USDC\u201d and \u201c-0.5 ETH.\u201d It is a prediction based on the current state of the network.<\/p>\r\n\r\n\r\n\r\n

That preview is useful for catching the wrong token, an unexpected amount, or a transfer you did not intend to make. But it is still only a prediction: a simulation does not prove that a contract is safe, and it does not guarantee that the onchain result will be identical<\/strong>. Network state can change, a malicious contract can deliberately behave differently during simulation, and some signatures or permissions do not move funds at the moment you approve them. That is why Estimated changes should be treated as one check, not the final verdict.<\/p>\r\n\r\n\r\n\r\n

What a MetaMask transaction simulation shows before you sign<\/h2>\r\n\r\n\r\n
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\"MetaMask<\/figure>\r\n<\/div>\r\n\r\n\r\n

MetaMask calls this feature estimated balance changes<\/strong><\/a>. In the confirmation screen, you will see it as Estimated changes<\/strong>. MetaMask simulates the transaction before it is submitted and shows the asset movements it expects.<\/p>\r\n\r\n\r\n\r\n

There are two details worth knowing before you rely on that preview:<\/p>\r\n\r\n\r\n\r\n