Cold email sending capacity calculator

500 cold emails a day needs 10 mailboxes across 5 sending domains. Each mailbox keeps 30 warmup emails reserved, so cold email is planned at 50 emails a day. The domain ceiling of 200 emails a day covers both. That is 500 cold emails a day on a new sending domain, with warmup left on. A new domain is capped at 200 emails a day in total. No account required.

WarmySender runs outreach on autopilot with AI agents across cold email, email warmup, LinkedIn, Instagram and multichannel sequences, plus real-time email verification. Adding a channel adds reach, not speed. When you need more cold email, add mailboxes and domains — do not push one mailbox past the default.

Domain ceilings

DomainCeilingWhat it means
A new sending domain200 a dayStarts small on purpose while the domain earns a reputation.
An established domain2,000 a dayThe steady state for a domain with a clean sending history.
A high-volume domain10,000 a dayFor domains with a long, clean record at scale.

The ceiling is shared by every mailbox on that domain, and warmup counts toward it. This page plans cold email at 50 a day per mailbox and reserves 30 warmup emails per mailbox unless you turn that off.

Common questions

How many mailboxes and domains do I need for a daily cold-email volume?

500 cold emails a day needs 10 mailboxes across 5 sending domains. Each mailbox keeps 30 warmup emails reserved, so cold email is planned at 50 emails a day. The domain ceiling of 200 emails a day covers both.

Why does warmup change how many domains I need?

Warmup and cold email share the domain's daily ceiling. With warmup left on, each mailbox reserves 30 warmup emails a day, which is the steady maintenance volume. Turn that off in the calculator only to see the cold-only figure — leaving warmup on is the safer plan.

Is 50 cold emails a day a provider limit?

No. 50 is the daily limit WarmySender sets on a new campaign mailbox. Google, Microsoft and Yahoo do not publish a per-mailbox cold-email cap. The limits this calculator applies are the domain ceilings: 200, 2,000, 10,000 a day.