Free deliverability toolbox

Inspect. Generate. Verify.

Practical DNS and content tools for email teams—free to use, deterministic where it matters, and clear about what each result means.

Start with the Email Domain Health CheckOne domain · 14 public authentication, infrastructure, reputation, and reporting checks · no mailbox access
Self-service diagnostics

Answer one technical question

Point-in-time investigation tools that never save evidence unless you deliberately move into a monitored workspace.

Domain audit

Email Domain Health Check

Audit one domain's public authentication, recursive SPF, spoofing exposure, DNS, mail routing, transport security, reporting, BIMI, certificates, and mail-IP reputation. This tool does not inspect individual mailboxes.

Verification

Email Verification

Check address format, receiving-domain mail routing, disposable domains, role addresses, and common spelling risks without unsafe mailbox probing.

Message

Delivered Message & Header Analyzer

Inspect authentication, MIME, HTML, links, attachments, message size, sending infrastructure, TLS, and the reconstructed delivery route.

Message

Send-to-Test Address

Create a temporary test address or paste a delivered message for complete authentication, route, MIME, HTML, link, and attachment analysis.

SPF

Recursive SPF Visualizer

Expand the complete SPF include graph and expose lookup cost, loops, duplicates, and failed branches.

DKIM

DKIM Selector Discovery

Check common and supplied selectors without mistaking one missing selector for absent DKIM.

Transport

BIMI Checker

Validate the BIMI DNS record and inspect its logo and evidence locations.

Transport

BIMI Logo Validator

Validate and normalize eligible SVG artwork for the BIMI Tiny-PS profile without uploading your logo.

Transport

BIMI Record Generator

Build a BIMI DNS record from your hosted logo and optional evidence certificate URLs.

Transport

MTA-STS Checker

Validate the DNS marker and HTTPS transport policy as one deployment.

Transport

MTA-STS Generator

Generate the DNS marker and HTTPS policy file for a staged SMTP transport policy.

Transport

TLS-RPT Checker

Inspect SMTP TLS reporting configuration and reporting destinations.

Transport

TLS-RPT Generator

Generate a TLS-RPT DNS record for email or HTTPS aggregate report delivery.

Risk

Spoofing Exposure Test

Safely model direct-domain spoofing exposure without sending forged email.

SPF

SPF Lookup

Find, parse, and validate the SPF policy published by a domain.

SPF

SPF Generator Wizard

Build an SPF record from the services that legitimately send mail for your domain.

SPF

SPF Raw Generator

Compose a precise SPF policy from mechanisms, networks, includes, and an all policy.

DKIM

DKIM Lookup

Inspect a DKIM public key at a domain and selector.

DKIM

DKIM Generator Wizard

Follow provider-specific instructions to enable DKIM without guessing tenant-specific DNS values.

DKIM

DKIM Raw Generator

Generate an RSA signing key pair and a publication-ready DKIM TXT record.

DMARC

DMARC Lookup

Inspect a domain's DMARC policy, alignment, rollout, and reporting configuration.

DMARC

DMARC Generator

Build a staged DMARC policy with reporting and alignment controls.

SPF

SPF Policy Validator

Validate a proposed SPF policy before publication, with syntax, mechanism, lookup-budget, and deployment findings.

DNS

DNS Evidence Explorer

Query common DNS record types through a selected public resolver and keep unavailable answers distinct from missing records.

Risk

Link Risk Investigator

Inspect URLs or message text for deceptive structure, redirect evidence, and configured threat-intelligence matches without declaring an unchecked link safe.

Reputation

IP & Domain Reputation Check

Check a public IPv4 address or domain against attributable email blocklist sources and link directly to each operator.

Reports

Private DMARC Report Analyzer

Analyze a DMARC aggregate XML or GZIP report in memory without saving its contents to a workspace.

Content & filters

Spam Filter Laboratory

Run explainable copy checks and configured filter engines with exact, attributable rule evidence.

Built for safe DNS changes

Lookups show live public evidence. Generators produce publishable fields, but remind operators to inventory senders, stage enforcement, and retain private DKIM keys securely.