Warm up your Mailgun inbox.
Mailgun routes the email — you build the reputation. Warmup Inbox handles the warming, automatically. Connect via SMTP credentials in minutes.
Why warm up your Mailgun inbox?
Mailgun delivers fast and reliably — but mailbox providers score reputation per sender domain, not per service. Cold outbound or sudden volume from a new Mailgun-routed domain hits spam filters until you build engagement history.
Mailgun infrastructure isn't enough
Gmail and Outlook don't trust the routing service — they trust the sender. New Mailgun domains start at zero reputation regardless of Mailgun's IP pool quality.
Warmup builds per-domain trust
Real inboxes engage with your Mailgun-routed sends. Reputation builds at the sender domain — exactly what spam filters score on.
What will you love about us?
Simplicity
Grab Mailgun SMTP credentials from the control panel, paste them in. Setup takes minutes — no API code required.
No fake inboxes
Real inboxes across every major mailbox provider — never bots. Your warmup partners look legitimate to spam filters.
Fair price
Plans start at $15/inbox/month annually. No unnecessary fees, no commitment.
Connect Mailgun in 30 seconds
SMTP credentials, three steps, you're warming.
Paste Mailgun SMTP credentials
In Mailgun, go to Sending → Domain settings → SMTP credentials. Generate or copy your credentials and paste them into Warmup Inbox.
Activate warmup
One click. Reputation builds across Gmail, Outlook, Yahoo from day one.
Frequently asked questions
Where do I find Mailgun SMTP credentials?
In the Mailgun control panel, go to Sending → Domain settings → SMTP credentials. You can use existing credentials or generate a new one specifically for Warmup Inbox.
Does this work with Mailgun's dedicated IPs?
Yes — and we recommend warmup more strongly for dedicated IPs. Dedicated IPs need warmup because you're building reputation on a fresh IP from zero, not piggybacking on a pre-warmed shared pool.
Will Mailgun's compliance flag warmup messages?
No. Warmup messages are real conversations between real inboxes — no spam patterns, no compliance triggers. The traffic looks like normal user-to-user email.
How does this affect my Mailgun pricing?
Warmup sends count against your Mailgun monthly send quota. Plan accordingly: a Pro Warmup Inbox plan adds about 7,500 messages/month per warming inbox.
How long until Mailgun reputation improves?
Most teams see open-rate and inbox-placement lift within 14–21 days. Brand-new Mailgun domains take 30–45 days for full warmup maturity.
Stop sending Mailgun emails to spam
Warm your Mailgun-routed inbox in minutes. Reputation builds; deliverability climbs; your campaigns reach the inbox.