MXToolbox

MXToolbox is best known for free DNS and blacklist checks, but the paid Delivery Center adds inbox placement analysis, complaint reporting, mailflow monitoring, configuration analysis, and domain impersonation protection. It is a practical utility layer for teams that want monitoring before a full DMARC suite.

At an early stage the deciding factors are what the free tier actually covers, what the first paid invoice looks like, and how much of a founding engineer's week the setup costs. Feature depth that only matters at a million sends a month is noise until it is not.

Against a waitlist, a launch announcement, onboarding email, and the first transactional sends, MXToolbox covers developer experience, and does not cover scheduling, SDK breadth, and webhook coverage. Whether that gap matters depends on how central those are to the build.

• Free tier: Free plan with 1 weekly blacklist monitor for 1 domain
• Best published rate per 1,000: Tiers not published in comparable form
• Starts at: $129/mo for Delivery Center with 5 domains and 500,000 message volume
• DX score: 6/10
• Deliverability: Not a sender. Useful for blacklist monitoring, configuration checks, inbox placement, complaint visibility, and sender reputation investigation.
• Operating since: Not published
• Scheduling: No
• SDKs: None
• Webhooks: No

Not a sender. Useful for blacklist monitoring, configuration checks, inbox placement, complaint visibility, and sender reputation investigation.

Teams that want DNS, blacklist, mailflow, and delivery monitoring in one utility platform.

A small sender that only needs basic DMARC report parsing.