Sendfeather Email Checker 作成者: Sendfeather

Sendfeather checks a domain's email setup the way mailbox providers do — MX, SPF, DKIM and DMARC — and explains what each record says in plain language.

Click the toolbar icon and the popup fills in the domain you are on (or type any domain). Each check gets a verdict — Passed, Review or Failed — with a short explanation of what the record means for delivery and, when something needs attention, what to fix first. Open a check's details to see the actual records found, DNS lookup counts, the DKIM selectors probed and where reports go.

Why it is different:
- Plain language, not scores. Every verdict states facts: which record exists, which policy is in force, and what receivers will do about it.
- Honest about limits. DKIM selectors are chosen by your sending provider; when the probe cannot find one, the extension says so instead of guessing.
- Private by design. Checks run in your browser against public DNS-over-HTTPS resolvers (Cloudflare, falling back to Google). Nothing is sent to Sendfeather or anyone else — no account, no analytics, no stored data.
- Minimal permissions. It reads the current tab's address only when you open the popup (to prefill the domain box) and can talk only to the two DNS endpoints.

Free. No account. Built by the team behind Sendfeather — email infrastructure on Amazon SES.

The full checker, with fix guides for every record, lives at https://sendfeather.com/tools/email-checker.