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Head to head · 2026

mailX vs SendHQ

Pricing, free plans, ratings, features, pros and cons, side by side. Where one comes out ahead, we mark it.

mailX

Free email deliverability checker that diagnoses SPF, DKIM, DMARC, and blacklist issues in one report

3.8Free

Visit mailX (opens mailX in a new tab)

SendHQ

Observable email infrastructure for product teams and AI agents

3.6$9/mo

Visit SendHQ (opens SendHQ in a new tab)

Who comes out ahead

Based only on the facts in our directory. The right pick still depends on the job you need done.

  • Lower starting price

    Not comparable

    Not comparable: mailX does not list a price

  • Free plan

    mailX

    Only mailX has one

  • Higher rating

    mailX

    3.8 against 3.6

  • Same job?

    Yes

    Both are AI Infrastructure & Agent Tooling tools

Side by side

Compared onmailXSendHQ
Our rating3.8Better3.6
Starts atFree$9/mo
Free planYesBetterNo
CategoryAI Infrastructure & Agent ToolingAI Infrastructure & Agent Tooling
PlansFreeFrom $9/mo
Key features
  • One-click SPF, DKIM, DMARC, MX, and blacklist checks
  • Consolidated deliverability report explaining spam placement causes
  • No signup or API key required for web use
  • JSON API for programmatic access
  • MCP server for direct use by AI agents
  • Developer API for sending and receiving transactional email
  • Separate inbox and sending identity per product, service or AI agent
  • Domain verification plus delivery and bounce tracking
  • Inbound mail routing and scoped API keys
  • Starter plan of 10,000 emails and 15 domains for $9 a month
Pros
  • Free with no signup barrier for a fast deliverability check
  • MCP server access is a differentiator most deliverability checkers lack
  • Backed by a Y Combinator company with deliverability-specific focus since 2020
  • Giving each AI agent its own inbox and identity suits agent-driven products
  • Low entry price for real sending volume
  • Inbound and outbound share one workspace
Cons
  • Narrow single-purpose scope rather than a full email marketing or sending platform
  • No paid tier means no dedicated support commitment for the tool itself
  • Deeper deliverability fixes still require action outside the tool, such as DNS changes or IP warmup
  • No free tier
  • Marketing email costs $10 a month more than transactional
  • Accounts with sustained high bounce or complaint rates are restricted
CompanyMailwarm, founded 2020Wavicle

Prices come from each vendor's pricing page, last checked 20260921. Check the vendor before you buy.

FAQ

Questions people ask

Is mailX better than SendHQ?

In our reviews mailX scores 3.8 and SendHQ scores 3.6. The better pick depends on the job. mailX: Free email deliverability checker that diagnoses SPF, DKIM, DMARC, and blacklist issues in one report. SendHQ: Observable email infrastructure for product teams and AI agents.

Which is cheaper, mailX or SendHQ?

mailX: free. SendHQ: from $9/mo.

Do mailX and SendHQ have free plans?

Only mailX has a free plan.

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