Clean your lists before you send. Draft & Check does a real SMTP mailbox check on every address, with catch-all and disposable detection and typo rescue, then returns a clear verdict and a 0 to 100 score. When it cannot confirm a mailbox it says "unknown" instead of a false "deliverable." Pay-as-you-go, credits never expire, and about 3 to 4x cheaper than ZeroBounce. Upload a CSV or use the API.