📧 Email Deliverability Checker
Check SPF, DKIM, DMARC and blacklist status for any domain
About Email Deliverability Checker
Email deliverability depends on three DNS-based authentication standards — SPF, DKIM, and DMARC — working together to prove your messages are legitimate. When these are misconfigured or missing, email providers treat your messages as suspicious, route them to spam, or reject them entirely.
This tool checks all five key signals in one pass: your SPF record (who is allowed to send), DKIM signing (message integrity), DMARC policy (what to do with failures), MX records (can you receive email), and blacklist status (is your sending IP flagged as spam). Each check includes a plain-English result and a specific fix if something is wrong.
How to Use This Tool
- 1 Enter your domain name (e.g.
yourdomain.com) — no http:// needed. - 2 Click Check Domain. The tool queries SPF, DKIM (20 selectors), DMARC, MX, and 4 blacklists simultaneously.
- 3 Review each card — ✅ pass, ⚠️ warning, ❌ fail. Each failure includes a specific plain-English fix.
- 4 Apply fixes in your DNS provider, wait for propagation, then re-run the checker to confirm.
Email Deliverability FAQ
What is an SPF record and why does it matter?
SPF (Sender Policy Framework) is a DNS TXT record that lists which mail servers are authorised to send email on behalf of your domain. Without it, spammers can forge emails that appear to come from your address.
What is DMARC and what policies are available?
DMARC (Domain-based Message Authentication, Reporting & Conformance) tells receiving servers what to do when SPF or DKIM checks fail. Policies: p=none (monitor only), p=quarantine (send to spam), p=reject (block outright). Start with "none" and move to "reject" over time.
Why is DKIM important?
DKIM (DomainKeys Identified Mail) adds a cryptographic signature to outgoing emails. Receiving servers verify this signature against a public key in your DNS. It prevents message tampering and increases trust with email providers.
What does it mean if my IP is on a blacklist?
Email blacklists are databases of IP addresses known to send spam. If your sending IP is listed, many email providers will block or heavily filter your messages. You need to submit a delisting request to each blacklist and address the root cause.
What is the SPF 10-lookup limit?
SPF resolution is limited to 10 DNS lookups. Each "include:", "a:", "mx:", "ptr:", or "exists:" mechanism counts as one lookup. Exceeding 10 causes a "permerror" which fails SPF checks. Use an SPF flattening service to stay under the limit.
How long do DNS changes take to propagate?
DNS changes can take anywhere from a few minutes to 48 hours to propagate globally, depending on the TTL (Time To Live) of the previous record. Lower TTL values speed up propagation. Run this checker again after making changes to verify they took effect.
Pro Tips
- • Deploy DMARC with p=none first. Monitor the rua reports for 2–4 weeks before moving to quarantine.
- • Use ~all (softfail) during SPF setup, then switch to -all (hardfail) once you have confirmed all senders.
- • Most email providers (Google, Microsoft, Mailchimp, etc.) give you a DKIM selector and TXT record to add to DNS.
- • Bounce rates above 2% cause exponential domain reputation damage — clean your lists before every send.
- • If you are blacklisted, check mail logs for spam complaints or open relay issues before requesting delisting.
- • Tools like MXToolbox and mail-tester.com can supplement this check with additional diagnostic data.