cold-email

Write cold emails that get responses. Ultra-short, signal-based, specific. Under 80 words — everything else is noise.

Phase 0: Sender Setup (Do Once)

Before sending a single cold email, your domain needs to pass authentication. Gmail, Yahoo, and Microsoft all reject non-compliant senders.

Required DNS records:

• SPF — v=spf1 include:youresp.com ~all (authorizes your sending server)
• DKIM — 2048-bit key, set up through your ESP (Resend, SendGrid, Postmark)
• DMARC — minimum v=DMARC1; p=none; rua=mailto:you@yourdomain.com

Domain warmup:

• New domain: start at 20–30 emails/day, ramp over 4–6 weeks
• Production limit: 50–100 emails per mailbox per day, never more
• Scale with multiple warmed mailboxes (3–5) rather than volume per mailbox