Use the 360 AIRO Mailbox Calculator to determine the ideal number of mailboxes, domains, and daily sending capacity needed to scale outreach safely. Mailbox planning helps protect deliverability while creating room for predictable pipeline growth.
Guidance
Use the 360 AIRO Mailbox Calculator to determine the ideal number of mailboxes, domains, and daily sending capacity needed to scale outreach safely. Mailbox planning helps protect deliverability while creating room for predictable pipeline growth.
Guidance
Mailbox providers monitor sending patterns, engagement, and reputation before deciding where your emails belong. Sending too much volume through a limited number of mailboxes increases the likelihood of spam placement and reputation damage. Proper mailbox distribution creates a healthier foundation for scaling cold outreach.
Guidance
Guidance
Many outbound campaigns fail because teams focus on volume instead of infrastructure. Before increasing sending activity, you need to understand the capacity of your domains and mailboxes. A mailbox calculator removes guesswork and provides a realistic roadmap for growth.
Guidance
The safest outbound programs distribute email volume across multiple mailboxes and domains. This approach reduces risk while creating sustainable growth. Instead of relying on a single inbox, build an infrastructure that can support long-term outreach.
Guidance
Different outreach goals require different infrastructure setups. Use these examples to understand how mailbox requirements scale with campaign volume.
Guidance
Mailbox infrastructure is only one part of the equation. Deliverability depends on how you manage volume, reputation, and engagement over time. Following best practices helps maintain inbox placement as you scale.
Guidance
Most companies wait until deliverability drops before fixing their email infrastructure. By then, sender reputation has already been damaged. The best outbound teams build mailbox capacity before they scale campaigns.
FAQ
A mailbox calculator estimates the number of mailboxes and domains required to safely achieve your outreach goals while maintaining healthy sender reputation.
Mailbox providers monitor sending behavior and may flag sudden volume increases as suspicious activity. Distributing volume helps reduce risk and improve deliverability.
Capacity varies depending on provider, domain reputation, mailbox age, and engagement levels. Mailboxes typically require proper warmup before reaching higher sending volumes.
For larger outreach programs, multiple domains help distribute risk and create additional sending capacity.
Yes. Every mailbox should establish its own sender reputation before being used for large-scale outreach.
Next step
Find out exactly how many mailboxes you need before you send another campaign. Protect deliverability, improve inbox placement, and build an outbound engine that scales without damaging your sender reputation.
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