Crypto glossary
Contract verification
Contract verification publishes a smart contract's source code and proves it compiles to the exact bytecode deployed on-chain, so anyone can read what it does.
A deployed contract is only bytecode. To verify it, the developer submits the source code, compiler version and settings to a service such as Etherscan, Blockscout or Sourcify. The service recompiles the code and checks that the output matches the bytecode at the address. If it does, the explorer shows the readable source, a verified badge and an interface for calling read and write functions directly.
Verification is a basic transparency signal in crypto. Auditors, researchers and users rely on it to check what a token or protocol can do, such as whether the owner can mint, pause or blacklist. Unverified contracts are a common red flag in token scanners, and many integrations and security tools only work with verified code.
Verified does not mean safe. Scam tokens are often verified, and malicious logic can hide in plain sight. For upgradeable proxies, the proxy may be verified while the implementation it points to changes later, so users must check the current implementation. Verification also says nothing about off-chain admin keys or how the team behaves.
Example
Before buying a new token, a user opens it on a block explorer, sees the contract is verified and finds a function that lets the owner block any address from selling.