Free Email Warmup — Not Needed On Mails.ai

Why warmup tools exist — and why there is nothing to warm here

Traditional email warmup tools exist to solve one problem: a new sending IP or domain with zero history looks suspicious to spam filters. To get past that, senders ramp volume over weeks and mail seed networks to manufacture engagement signals. It is slow, fragile, and yours to manage.

Mails.ai removes the problem instead of selling you a tool for it. Your agent sends from agent.yourworkspace@send.mails.ai on a shared rail that is already warm: a real record of transactional sending, low complaint rates and verified authentication. Your first message goes out on that record. There is no ramp to wait through.

What happens when you bring your own domain

Sending as notifications@yourapp.com is different, and this is where most warmup marketing is dishonest. A brand-new domain has no standing of its own, and no vendor can create one for you — mailbox providers weight real opens, replies and complaints from real people. Seed-network mail builds a pattern, not a reputation.

What you actually get:

• A DKIM keypair generated for your domain automatically — you publish one DNS record
• Delivery over mail servers we rent and keep warm, rather than a cold box rented this morning
• SPF guidance that merges with your existing record instead of replacing it, so your current email keeps working
• No nameserver move, and no seed network anywhere in the path

Your domain’s own standing then builds the only way it can: with the real mail your product sends. One limit worth knowing before you set this up — mail from a custom domain cannot reach Outlook or Hotmail recipients yet. Mail from the shared send.mails.ai domain reaches them normally.

# Add your domain (any paid plan) — we return the DNS records to create
curl https://api.mails.ai/v1/domains \
  -H "Authorization: Bearer $MAILS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"domain": "mail.yourapp.com"}'

# Publish the DKIM record at your registrar, then check status
curl https://api.mails.ai/v1/domains/dom_123 \
  -H "Authorization: Bearer $MAILS_API_KEY"

# {
#   "id": "dom_123",
#   "domain": "mail.yourapp.com",
#   "status": "verifying",        // pending -> verifying -> verified
#   "provider": "ownmetal",
#   "dns_records": [
#     { "type": "TXT", "host": "dkim._domainkey.mail.yourapp.com",
#       "purpose": "dkim", "required": true, "verified": false }
#   ],
#   "fail_reason": "dkim record missing or mismatched (dkim._domainkey.mail.yourapp.com)"
# }

What it costs

Nothing, to start. The free tier is $0/mo and covers 3,000 emails and 3,000 inbound replies a month, and one agent on the shared sending domain — warm rail included, because that is simply how the product sends. Sending from your own domain is on the paid plans, from $20/mo, which also lifts you to five agents. Agents that do not have a domain yet start on their own AI email address and need no warmup at all.

Want reputation isolated from the shared pool entirely? A dedicated IP is available on request on the Scale plan. It is worth being blunt about when that helps: a dedicated IP only earns a reputation if you give it steady volume, so below roughly a few hundred thousand messages a month you are usually better off on the warm shared rail. For the full comparison against standalone tools, see email warmup service.