Klaviyo
klaviyo.com
Email and SMS built around e-commerce data
from $20/moFree plan
Mails.ai
Email API and inbox infrastructure for AI agents
Free plan availableEmail MarketingSince 2025
from $20/moVisit mails.ai
What Mails.ai is
Gives an AI agent a real mailbox: inbound arrives as structured reply events carrying a prompt-injection score and sender reputation, with a six-category injection scanner on every message, dedicated IPs and an MCP server. Cold email is refused at the API rather than in the fine print.
Mails.ai's Pro plan has read $20 on every one of the 3 times we have checked this page, from Aug 2026 to Sept 2026. It has not moved while we have been looking. See the source
People use it to
Current offers
Free plan
Free plan, no card required
Ongoing free tier published by the vendor. Limits vary by plan.
Mails.ai alternatives
Other tools in email marketing that cover similar ground. Full comparison.
Where Mails.ai sits on price
Entry prices across Email Marketing, cheapest first.
- Brevo$10.80
- MailerLite$12
- Mailchimp$13
- ActiveCampaign$15*
- Postmark$15
- Klaviyo$20*
- Mails.ai$20
- Resend$20
- SendGrid$20*
- Kit$33
8 of these 12 prices were read from the vendor's own pricing page; the rest are marked * and are indicative. The median is taken across the 7 verified prices in Email Marketing. Showing the 10 cheapest.
Mails.ai pricing questions
- How much does Mails.ai cost?
- Mails.ai starts at $20 a month on its Pro plan. That figure was read from mails.ai's own pricing page on 21 September 2026.
- Does Mails.ai have a free plan?
- Yes. Mails.ai publishes an ongoing free tier — not a countdown trial. Limits vary by plan, so check what the free tier covers before you commit.
- What is Mails.ai used for?
- Gives an AI agent a real mailbox: inbound arrives as structured reply events carrying a prompt-injection score and sender reputation, with a six-category injection scanner on every message, dedicated IPs and an MCP server. Cold email is refused at the API rather than in the fine print. People mainly use it to send transactional email, give an agent an inbox, scan inbound for prompt injection.
- What are the best alternatives to Mails.ai?
- The closest alternatives in the same category are Klaviyo, Mailchimp, Kit, ActiveCampaign. Mailchimp starts lower at $13 a month; ActiveCampaign starts lower at $15 a month. Klaviyo, Mailchimp and Kit publish a free plan.