Definition
Multi-sig, short for multi-signature, is a cryptocurrency security concept where multiple independent signatures are needed to authorize a transaction. Instead of relying on a single private key, a multi-sig arrangement distributes control across several keys held by different people, devices, or locations. A predefined rule, such as “2-of-3” or “3-of-5” signatures required, determines how many approvals are needed before funds can move. This structure reduces the risk that a single compromised key or lost device can unilaterally control or drain an account.
In a multi-sig setup, the wallet or smart contract is configured so that it will only broadcast and finalize a transaction once the required number of valid signatures has been collected. The underlying blockchain verifies that the correct combination of keys has signed according to the agreed rule. Multi-sig is commonly used for shared accounts, organizational treasuries, and higher-security personal storage. It is a foundational security concept that adds redundancy and shared control to crypto asset management.
In Simple Terms
Multi-sig is like putting several locks on the same digital safe, where more than one key must be used before the safe opens. No single person or device can move the funds alone, because the rules require multiple approvals. This makes it harder for thieves, hackers, or simple mistakes to cause a total loss of funds. By spreading control across several keys, multi-sig turns a single point of failure into a shared responsibility model.