See your sender reputation score the way Gmail, Outlook, and Yahoo do
We grade the exact signals mailbox providers weigh: SPF, DKIM, DMARC, blacklist status, and DNS. Check any domain free and get an A to F grade in seconds, with a prioritized fix list.
How to check your sender reputation
No account, no installation. Enter a domain and we do the rest in seconds.
Enter your domain
Type any domain you send from. There is nothing to install and no signup, so you can check a domain in seconds.
We run every check
We query live DNS for SPF, DKIM, DMARC, blacklists, MX, and reverse DNS, the same signals mailbox providers weigh.
Get your grade and fixes
You receive an A to F Sender Reputation Score with a category breakdown and the exact, prioritized fixes that move the needle.
Free email deliverability tools
Diagnose every signal behind your sender reputation, one tool at a time.
Sender Reputation Checker
Your free A to F grade across authentication, blacklists, DNS, and infrastructure.
Check your domainSPF Record Checker
Validate syntax and count DNS lookups against the limit of 10.
Check SPFDKIM Record Checker
Confirm your DKIM key is published and using strong encryption.
Check DKIMDMARC Record Checker
Inspect your policy, alignment, and aggregate reporting.
Check DMARCBlacklist Checker
Scan the major DNS blacklists for a domain or IP address.
Scan blacklistsMX Lookup
Show mail server records, priorities, and redundancy.
Look up MXReverse DNS Checker
Confirm PTR records are present and forward-confirmed.
Check rDNSEmail Header Analyzer
Trace the delivery path and read authentication results.
Analyze headersLearn email deliverability
In depth, plain language guides to authentication, reputation, and reaching the inbox.
Email deliverability insights
News, tips, and practical guidance for senders who want to reach the inbox.
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