Validate byte length and explain what a checksum does.
LET’S PICTURE IT
A spelling check can catch a typo without proving the recipient is trustworthy.
SEE IT FOR YOURSELF
From a public address to a verified signatureStep 1 / 4
An address is public receiving information. It is not the private key that authorizes actions.
An address is public receiving information. It is not the private key that authorizes actions.The local signing system uses secret authorization material. It produces a signature; the private key is not sent along with it.A verifier checks the signed request under the account’s rules. A valid signature does not by itself prove that the action is safe.Balances belong to network state. A wallet is an interface and signing system, not a box containing coins.
Animated local teaching model. No wallet, RPC or live blockchain data. Some labels and hashes are abbreviated for readability.
Separate format validation
An Ethereum address has twenty bytes. Validate the hexadecimal form and expected length before presenting a checksum result.
Apply the correct checksum convention
EIP-55 uses Keccak-256 of the lowercase hexadecimal address text without the prefix to choose letter casing. Use a tested implementation and known fixtures.
Explain acceptance policy
Libraries differ in how they accept uniform-case and mixed-case input. State the chosen policy and reject a mixed-case checksum mismatch where that policy requires it.
Keep conclusions narrow
The tool does not prove ownership, network deployment, balance or safety. It should not resolve names or connect a wallet merely to perform a formatting check.
Your acceptance target
input: public 20-byte address
output: validated format + EIP-55 display
reject: malformed hex or incorrect length
no balance or ownership claim
Use only local examples and public sample addresses. State the assumptions and limits alongside the result.