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What is a verified contract?
A verified contract is a smart contract whose source code has been published and shown to compile to exactly the bytecode deployed on the blockchain. Block explorers mark such contracts, so anyone can read the human-readable code behind an address instead of raw machine code.
What it means for you
Verification lets you, or someone you rely on, read what a contract will do with your tokens before you approve it. It does not mean the code is secure or honest: a verified contract can still contain a bug, an admin key or a drain function in plain sight. An unverified contract asking for an approval keeps its code hidden from you.
A common mistake: “The contract is verified, so it has been checked and is fine.”
In fact: Verified only means the published source matches the deployed bytecode. Nobody has necessarily reviewed it, and malicious code can be verified just as easily as honest code.
How it works
To verify, a developer submits the source files and compiler settings; the verifier recompiles them and compares the result with the bytecode at the contract's address. Most services perform a partial match, comparing the functional bytecode. A full match also compares the metadata hash the compiler appends, which captures the source files and settings, so not a single byte differs from the original compilation. Verification confirms that the published source is what is deployed; it says nothing about whether that code has vulnerabilities or works as intended. That review is the job of an audit.
Sources: ethereum.org: Verifying smart contracts, ethereum.org: Smart contract security · checked 4 October 2026
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Educational content, not financial advice. Written by hand and checked against the source named above. Something wrong? Tell us and we reply within two business days.