Postscale Check · free diagnostics

Free email and invoice tools

Check SPF, DKIM, DMARC, MTA-STS and TLS-RPT records. Parse DMARC reports, decode headers, validate XRechnung XML, and convert provider snippets.

Email authentication check

MX, SPF, DKIM, DMARC, MTA-STS, TLS-RPT

Run a combined Postscale Check for the records receivers inspect before trusting mail from a domain, including SMTP TLS policy and aggregate TLS reporting.

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SPF record checker

Parse and validate SPF

Walk a domain's SPF include/redirect tree, count DNS lookups against the 10-lookup budget, and spot records that will permerror at receivers.

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DKIM record lookup

Inspect DKIM public keys

Enter a domain and selector to see the published TXT record, parsed key type, approximate key size, and warnings on revoked or weak keys.

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DMARC check

Score DMARC enforcement maturity

Fetch a domain's DMARC record, see the parsed policy, get a 0–5 maturity score, and receive concrete next-step recommendations.

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DMARC aggregate parser

Parse RUA XML reports

Paste or upload a DMARC aggregate (RUA) XML report to see per-source records, DKIM/SPF alignment, and the aggregate pass rate. No uploads.

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XRechnung validator

Validate EN 16931 XML

Paste or choose an XRechnung UBL/CII XML invoice and run Postscale's EN 16931/XRechnung preflight checks before sending or ingesting it.

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Email headers analyzer

Decode raw email headers

Paste raw email headers to see the routing hop chain with timing, authentication results (SPF/DKIM/DMARC/ARC), and every parsed field.

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Email API migration converter

Convert provider snippets

Translate common SendGrid, Mailgun, Postmark, Resend, and SES send calls, webhook adapters, SMTP settings, and suppression CSV exports into Postscale-ready snippets.

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Why we built these

Every time we help a new customer onboard, we run the same sequence of checks: parse their SPF, confirm their DKIM key isn't expired, make sure their DMARC is recording reports to a mailbox we can read. We used to run these from the terminal; now they live as free diagnostics so you can too. No account required.

If you end up needing this functionality in production — parsing DMARC reports nightly, monitoring DKIM rotations, alerting when a new sending source appears — that's what our product APIs are for.

Automate this?

When the one-off tools stop scaling, Postscale's APIs pick up — DMARC reporting, inbound email, transactional sending, masked addresses, XRechnung e-invoicing.

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