Question 1

How many emails can I send per mailbox per day?

Accepted Answer

Best practice for cold email is to send no more than 30-50 emails per mailbox per day. ColdRelay uses a conservative limit of ~30 emails per mailbox to maintain optimal deliverability. This calculator uses 4 emails per mailbox as a safe daily average accounting for warmup and ramp periods.

Question 2

Why do I need multiple domains?

Accepted Answer

Sending cold email from your primary domain risks its reputation. Using dedicated sending domains protects your brand. We recommend no more than 2-3 mailboxes per domain for cold outreach, but this calculator assumes up to 150 mailboxes per domain as an upper bound for infrastructure planning.

Question 3

How much does ColdRelay cost compared to Google Workspace?

Accepted Answer

ColdRelay starts at $1/mailbox/month for small volumes and drops to $0.55/mailbox/month at scale. Google Workspace costs $7.20/user/month and Microsoft 365 costs $6/user/month. At 100 mailboxes, ColdRelay saves you over $600/month compared to Google.

Question 4

What's included in ColdRelay's mailbox pricing?

Accepted Answer

Every ColdRelay mailbox includes automated domain setup, DNS configuration (SPF, DKIM, DMARC), mailbox warmup, deliverability monitoring, and rotation — all managed for you. Google and Outlook charge extra or don't offer these features at all.

Question 5

Can I start small and scale up?

Accepted Answer

Absolutely. Start with a few mailboxes on the Starter tier and scale to hundreds or thousands. ColdRelay automatically moves you to lower per-mailbox pricing as you grow. No contracts or commitments.

Cold Email Mailbox Calculator

Monthly Cost Comparison

ColdRelay Pricing Tiers

Frequently Asked Questions

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