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Bulk DNS & Email
MX Checker Tool

Check MX, SPF, DMARC, DKIM, A, NS records for hundreds of domains. Validate emails and detect providers like Gmail, Yahoo & Outlook. Export to CSV instantly.

3,500
Total Checks
205
Checked Today
0
Last Hour
793
Domains Scanned

All Tools

All free — no login needed — up to 500 domains per check

📧 Email Authentication
🌐 DNS Records
🔄 Reverse DNS & Audit

Why Use BulkDNS?

Everything you need to audit DNS and email records at scale

Lightning Fast
40 concurrent DNS threads — 500 domains in under 15 seconds.
📁
CSV Upload & Export
Import domain or email lists from .csv or .txt files. Export full results instantly.
🔓
100% Free Forever
No account, no credit card, no rate limits. Just paste and go.
📊
Provider Analytics
See Gmail, Yahoo, Outlook & more breakdown across your email list.
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Email Security Audit
Check SPF, DMARC and DKIM to protect domains from spoofing.
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All DNS Record Types
MX, SPF, DMARC, DKIM, A, AAAA, NS, CNAME, TXT, SOA and PTR.

What is a Bulk DNS Checker?

A bulk DNS checker is a tool that lets you look up DNS records for dozens or hundreds of domains simultaneously. Instead of checking them one by one in a terminal or online tool, you paste or upload your list and get instant results — saving hours of manual work for sysadmins, email marketers, and developers.

Our tool supports all major DNS record types: MX (mail servers), SPF (sender policy), DMARC (email policy), DKIM (signing keys), A (IPv4), AAAA (IPv6), NS (nameservers), CNAME (aliases), TXT (text records), SOA (zone authority), and PTR (reverse DNS).

What is the Email MX Checker?

The Email MX Checker is our newest tool. Upload or paste a list of email addresses and it will validate the format of each one, look up MX records for each unique domain, and automatically classify the email provider — Gmail, Yahoo, Outlook, ProtonMail, Zoho, Amazon SES and more. You get a full provider breakdown chart and can download the results as a CSV file.

This is ideal for email marketers who want to understand their list composition, developers validating sign-up forms, and anyone cleaning bulk email lists before a campaign.

How to Use This Tool

  1. Choose a tool from the list above (e.g. MX Lookup or Email MX Checker)
  2. Paste your domains or email addresses — one per line — or upload a .csv / .txt file
  3. Click Run and results appear in seconds
  4. Click Download CSV to export the full results

FAQ

Is it really free?

Yes — completely free. No account, no credit card, no hidden limits. Up to 500 domains or emails per request.

How many domains can I check?

Up to 500 domains or emails per request. Duplicates are automatically removed.

Does Email MX verify mailboxes?

No — it checks format validity and MX DNS records. SMTP-level mailbox verification is blocked by most mail servers.

Can I upload a file?

Yes — upload any .csv or .txt file. Comma, semicolon or newline separated lists all work.

Why check SPF & DMARC?

They protect your domain from email spoofing. Missing SPF/DMARC means your emails may land in spam or attackers can impersonate your domain.