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.

A SaaS product sends on behalf of its customers, so the deciding factors are tenant isolation, whether suppressions can be scoped rather than global, and whether support can answer why one specific account did not receive one specific email. Lifecycle automation and transactional sending usually need to coexist.

Against trial expiry notices, dunning, onboarding sequences, and per-tenant transactional mail, MXToolbox covers event stream, and does not cover multi-tenant support, the suppressions API, scheduling, and webhook coverage. Whether that gap matters depends on how central those are to the build.

• Multi-tenant: No
• Event stream: Yes
• Suppressions API: No
• Operating since: Not published
• Scheduling: No
• Best published rate per 1,000: Tiers not published in comparable form
• Deliverability: Not a sender. Useful for blacklist monitoring, configuration checks, inbox placement, complaint visibility, and sender reputation investigation.
• Webhooks: No
• Starts at: $129/mo for Delivery Center with 5 domains and 500,000 message volume

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.