Inbox Warmup vs Mailwarmup

Inbox Warmup connects SMTP infrastructure, authenticates domains, warms sending activity, monitors reputation signals, manages replies, and controls campaigns from a web and API dashboard. It supports SMTP ports 465 with SSL/TLS, 587 with STARTTLS, and compatible custom ports. Checks include SPF, DKIM, DMARC, Return-Path, ownership, and tracking records. Warm-up automation increases activity gradually, rotates sending, respects mailbox limits, and can pause when health signals need attention. Campaign tools provide templates, personalization, timezone scheduling, hourly and daily limits, and pause or resume controls. Listed mailbox providers include Gmail, Workspace, Outlook, Yahoo, and IMAP accounts, with Google Postmaster and Yahoo sender-data integrations. Launch costs $39 a month after a $1 first seven days; Growth is $99 a month and Professional $199 a month on the same terms. Agency pricing is custom. Credits reset monthly and do not roll over.

Mailwarmup is a web service that aims to raise sender reputation by generating positive email engagement through a shared network of more than 10,000 inboxes. After users connect an account using SMTP and IMAP details, it sends scheduled messages on their behalf. Network inboxes open and reply to messages, mark them important, and remove them from spam. A dashboard tracks warmup results, including messages removed from spam, categories, and email deliverability. Listed integrations include Gmail, Outlook, and SMTP; users can control sending and limits. Other listed tools include a Mail Health Score, blacklist monitoring, delivery statistics, blacklist removal prompts, and AI ramp ups in beta. Warmup messages can be filtered into a separate folder using the subject keyword “WUA.” There is no free plan, but a 7-day trial is offered. Starter costs $19 a month for one email account and up to 50 positive engagements per day. Growth is $49 a month for three accounts and up to 50 engagements daily; Scale is $99 a month for eight accounts and up to 100 daily; Powerhouse is $149 a month for eight accounts and up to 300 daily. Warmup does not guarantee inbox placement.