Deliverability Monitor

Catch the misconfiguration before receivers do.

Blacklist status tells you when your reputation is already damaged. SenderSignal's hourly checks on SPF, DKIM, DMARC, MTA-STS, BIMI, TLS, MX and PTR catch the misconfigurations that damage it, before a single receiver notices.

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monitor · deliverability · acme.io
Hourly sweep8/9 passing
The check matrix

Every layer of the sending stack, on a schedule.

Each asset is re-swept every 60 minutes by default, and every result is diffed against the previous run, so you hear about the change, not just the state.

LayerChecks per domainWhat it catches
RoutingMX records with change detectionSilent MX swaps, provider migrations gone wrong
TransportSMTP (port 25) reachability, STARTTLS negotiation, TLS certificate expiry warningsCerts expiring before they take mail down
AuthenticationSPF parse & validation, DKIM, DMARC policy parse including policy strengthBroken includes, missing selectors, weakened policies
Policy & brandMTA-STS, BIMIStrict-transport and brand-indicator regressions
Per sending IPPTR record, forward-confirmed reverse DNS (FCrDNS), IP SMTP reachability, DNSBL presenceHygiene failures many receivers reject on
ESP detection

It knows what you send with, and what that should look like.

SenderSignal fingerprints which email service provider a domain uses against a catalog of 51 ESPs, so check results are read in the context of your actual stack instead of generic rules.

  • 51-ESP catalog, Klaviyo, Mailchimp, SendGrid, Amazon SES, Google Workspace, Microsoft 365, Zoho and more
  • Three fingerprints, SPF includes, DKIM selectors and MX signatures identify the provider
  • Change-aware, every sweep is compared to the last, so a swapped MX or weakened DMARC policy stands out
  • ~60 alert event types, MX changed, cert expiring, DMARC policy weakened and more feed straight from these checks
esp detection · acme.io
By the numbers

Continuous, not occasional.

Deliverability monitoring is included on paid plans (professional and up), and every new-workspace 30-day trial includes it.

60 min
Default check interval, every asset re-swept hourly
51
ESPs recognized via SPF includes, DKIM selectors and MX signatures
~60
Alert event types across the platform fed by these checks
30 days
New-workspace trial, deliverability monitoring included
Goes well with

Configuration is the cause; reputation is the effect.

Feature

Blacklist monitoring

48 blacklist & reputation sources, scored 0-100 with trend history.

Learn more Feature

Sender reputation

Google Postmaster reputation, spam rate and compliance in one view.

Learn more Feature

Guided DNS setup

Generate, verify and publish SPF/DKIM/DMARC records in one click.

Learn more
Use case

SaaS & transactional

Keep resets, receipts and notifications out of the spam folder.

See the playbook Use case

Agencies

Monitor every client from one login, with white-label reports.

See the playbook
Questions

Deliverability monitoring, explained.

What exactly gets checked on a domain?
Every monitored domain is continuously checked for MX records (with change detection), SMTP reachability on port 25, STARTTLS negotiation, TLS certificate expiry, SPF record parsing and validation, DKIM, DMARC policy parsing including policy strength, MTA-STS and BIMI.
What about sending IPs?
IP assets get their own checks: PTR record presence, forward-confirmed reverse DNS (FCrDNS), SMTP reachability on the IP itself, and presence on DNS blocklists. Many receivers treat missing PTR or failing FCrDNS as a basic hygiene failure.
How often do deliverability checks run?
The default deliverability check interval is hourly, every 60 minutes, each asset is re-swept and any change is compared against the previous state so you get alerted on the delta, not just the current status.
How does ESP detection work?
SenderSignal recognizes which email service provider a domain uses via a catalog of 51 ESPs, Klaviyo, Mailchimp, SendGrid, Amazon SES, Google Workspace, Microsoft 365, Zoho and more, by matching SPF includes, DKIM selectors and MX signatures.
What kind of alerts do these checks produce?
Roughly 60 alert event types across the platform feed from these checks, for example MX changed, TLS certificate expiring, or DMARC policy weakened. Alerts fire to your configured channels the moment a check detects a change.
Is deliverability monitoring included on my plan?
It is included on paid plans (professional and up), and every new workspace gets a 30-day trial that includes deliverability monitoring, so you can see your full check results before deciding.
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See your first sweep within the hour.

Add a domain and the full check matrix runs, new workspaces get a 30-day trial that includes deliverability monitoring.

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