Bulk Mail Records Checker (SPF, DKIM, DMARC, MX)
Email deliverability lives and dies on three DNS records.
More about this tool
SPF lists the servers allowed to send mail for the domain; DMARC tells receiving servers what to do when SPF or DKIM fail, from silent monitoring to full rejection; DKIM cryptographically signs messages so forwarding does not break authentication. A missing or misconfigured record means newsletters land in spam and — worse — anyone can spoof the domain in phishing campaigns. This bulk checker resolves the mail setup for every domain in your list: MX servers with priorities, the full SPF record with its policy qualifier (how strictly the all mechanism ends), the DMARC record with its policy, and DKIM keys for the common selectors used by popular mail providers. It is the fastest way to onboard acquired domains, to verify a migration to a new mailing service, or to audit a whole portfolio before a campaign. Domains without any mail setup are marked, so a silent absence of SPF — the classic post-migration surprise — is impossible to miss. The report exports to CSV.
How it works
- Paste up to 100 items, one per line. Duplicates are removed automatically.
- If a line contains a full URL, only its host name is used.
- The check runs in the background; the results page shows live progress.
- Filter the report by status code and export it to CSV.
Rate limit: 5 jobs per hour from one IP address. Results are stored for 7 days.
FAQ
Why does SPF policy matter?
The ending mechanism decides what happens to senders not on the list: -all rejects them, ~all marks as suspicious (softfail), +all allows everyone. A softfail is a common transitional state, but an SPF ending in +all is the same as having no SPF at all.
What DMARC policy should I use?
p=none only collects reports without acting — good for the first weeks. p=quarantine moves failing mail to spam, p=reject drops it. Most established senders end up at reject; starting straight at reject without monitoring reports is risky.
Why is DKIM "not found" when the domain sends signed mail?
DKIM records live at selector subdomains, and the selector is chosen by the sending system — often a custom one. The checker probes the eight most common selectors; if your service uses its own, the record exists but is invisible here. The field says "probed", not "absent".
A domain without MX — is that an error?
Not always: a domain used only for sending or for a website may legitimately have no MX. The report marks "mail not configured" so such domains stand out in the list — whether that is fine is your call.
Can this check break email?
No — it only reads DNS records, changing nothing. It is the same kind of lookup any mail server performs thousands of times a day.
Other tools
Bulk Domain Blacklist Checker (DNSBL)
Free bulk blacklist checker: paste domains and check them against Spamhaus, Barracuda, SpamCop, SORBS and SURBL in one run. Instantly see if your domain or IP is blacklisted. CSV export.
Accepts a list of domainsBulk DNS Records Lookup (A, AAAA, MX, NS, TXT)
Free bulk DNS lookup with a custom DNS server option: paste domains and get A, AAAA, CNAME, MX, NS, TXT, SOA and SRV records grouped by type, one record per line with TTL, MX priorities, copy buttons and CSV export.
Accepts a list of domainsBulk Domain Expiration Checker (RDAP)
Free bulk domain expiry checker via RDAP with automatic WHOIS fallback: paste a list of domains and get the registrar, registration and expiration dates and days left for each. Domains expiring within 30 days are highlighted. Registry answers are cached for 24 hours. CSV export included.
Accepts a list of domainsBulk URL Status Checker
Free bulk URL status checker: paste up to 100 URLs and get HTTP status codes, redirect chains, final URLs and response times. Export the results to CSV.
Accepts a list of URLsBulk Indexability Checker (noindex, X-Robots-Tag, canonical)
Free bulk indexability checker: paste URLs and detect noindex meta tags, X-Robots-Tag headers, nofollow, canonical and hreflang. Export the crawl audit to CSV.
Accepts a list of URLsBulk Meta Tags Checker (Title, Description, H1)
Free bulk meta tags checker: paste URLs and get Title, meta description, H1 and heading counts with length checks and duplicate detection. Export the SEO audit to CSV.
Accepts a list of URLsBulk Open Graph & Twitter Cards Checker
Free bulk Open Graph checker: paste URLs and audit og:title, og:description, og:image, twitter:card and more social preview tags. Export the report to CSV.
Accepts a list of URLsBulk Outgoing Links & Broken Links Checker
Free bulk outgoing links checker: paste URLs to count external and internal links, dofollow vs nofollow, and find broken links (404, 5xx, dead domains). Export the audit to CSV.
Accepts a list of URLsBulk robots.txt Checker
Free bulk robots.txt checker: paste a list of domains and see the status of /robots.txt, redirect count, file size, the number of Sitemap directives and whether all crawlers are blocked. CSV export included.
Accepts a list of domainsBulk Security Headers Checker (HSTS, CSP)
Free bulk security headers checker: paste domains and audit HSTS, X-Content-Type-Options, CSP, X-Frame-Options, Referrer-Policy, Permissions-Policy and the HTTPS redirect. CSV export.
Accepts a list of domainsBulk SSL Certificate Checker
Free bulk SSL certificate checker: paste a list of domains and instantly see the certificate subject, issuer, hostname match, expiry date and days left before renewal. Find expiring certificates before they become incidents. CSV export included.
Accepts a list of domainsBulk TTFB & Speed Checker
Free bulk TTFB checker: paste a list of URLs and measure time to first byte, total response time and HTML size for each page. Export the report to CSV.
Accepts a list of URLs