WarmInbox — Email Warmup

About

Most warmup services cost $29 per mailbox each month. WarmInbox offers three mailboxes on its Starter plan for that price, and ten mailboxes on the Pro plan for $79. It connects using SMTP or IMAP, sends daily realistic emails between real accounts, marks them as read, and replies to 40% of them. Your warmup score progresses from 0 to 100 over a four week period. It works with Gmail, Outlook, and custom domains. A free plan is available with one mailbox and no credit card needed.