Email Provider & ISP Breakdown Analyzer

Paste your email or domain list and instantly see the provider breakdown across Gmail, Microsoft 365, Yahoo, and more using live MX record lookups.

Know exactly which inbox providers your list sends to before you hit send.

Email Tester Inbox Placement Tester

Upload or paste your email or domain list (up to 500 entries) to analyze MX records and gain insights into email providers like Gmail, Outlook, and more. For domain lists, keep duplicates to ensure accurate provider counts. One email or domain per row. For no file size restrictions, unlimited usage, and identification of spamtrap and disposable email domains, please create an account and purchase any subscription package.

Analyze Providers
Paste or drag and drop in your Email or Domain File below and then click the "Analyze Providers" Button:
Total Rows: 0
Built with ♥ by Henry Timmes · Named contributor to RFC 7489 (DMARC)

Why Your Email Provider Breakdown Matters for Deliverability

Not all inbox providers filter email the same way. Gmail, Microsoft 365, Yahoo, and corporate security gateways like Proofpoint and Mimecast each use different spam scoring algorithms, reputation signals, and engagement thresholds. A campaign that lands perfectly in Gmail inboxes can simultaneously be going to spam for every Microsoft 365 recipient on your list.

This tool performs live MX record lookups on your email or domain list and shows you the exact split. When deliverability drops, that breakdown tells you exactly which provider to investigate first.

🔎

Identify Provider Concentration

Find out if 60% of your list routes through Microsoft 365, or if a large chunk uses corporate security gateways. Concentration in one provider is a deliverability risk you need to know about.

📊

Compare Full List vs. Opens List

Run the tool on your full list, then again on just your openers. If Microsoft 365 makes up 40% of your list but only 15% of opens, that gap points to a targeted O365 deliverability problem, not a content issue.

🎯

Prioritize Your Fix

Different providers require different remediation. Gmail issues often come down to engagement and sender reputation. Microsoft 365 problems frequently need direct escalation. Knowing which provider is blocking you is step one.

How to Use This Tool

  1. Paste your email list or domain list (one per row) into the text area above. Up to 500 entries free.
  2. Click Analyze Providers to run live MX lookups on each domain
  3. Review the provider breakdown in the results table
  4. Download a summary or full detail report for further analysis
  5. Repeat with just your opens list and compare the two distributions to find where deliverability is dropping

Tip: For domain lists, keep duplicate domains in your paste. Each row represents one contact, so duplicates are needed to get an accurate count of how many people use each provider rather than just a count of unique domains.

Frequently Asked Questions

An MX (Mail Exchange) record is a DNS entry that identifies which mail server handles incoming email for a domain. For email marketers it reveals which inbox provider your contacts actually use, regardless of what the email address looks like. A contact at company.com might be hosted on Microsoft 365, Google Workspace, or a corporate gateway. Knowing your MX provider split tells you which spam filters your emails must pass.

Each major inbox provider uses different spam filtering logic with different thresholds and signals. If 60% of your list routes through Microsoft 365 and you have a problem there, you'll see a sharp drop in opens from that segment while Gmail performance stays normal. Knowing your provider split is the first step in diagnosing exactly where your deliverability is breaking down.

Run the tool twice: once on your full list and once on your opens list from a recent campaign. Compare the provider breakdown between the two. If your full list is 40% Microsoft 365 but your opens list shows only 15% Microsoft 365, your emails are likely landing in spam for O365 recipients. This technique pinpoints which provider is causing the problem without needing specialized inbox placement software.

You can paste either full email addresses (user@company.com) or just domains (company.com). When you paste email addresses the tool extracts the domain and performs the MX lookup. If you paste raw domains, keep duplicates. Each row represents one contact, so duplicates are needed to get an accurate count of how many people use each provider rather than just a count of unique domains.

The tool identifies all major providers including Gmail, Google Workspace, Microsoft 365, Exchange Online, Yahoo Mail, Outlook.com, Hotmail, iCloud, Zoho Mail, ProtonMail, and hundreds of smaller regional ISPs and corporate mail servers. Any provider with a detectable MX record pattern will be categorized and counted.

The free version supports up to 500 entries per batch with no account required. For unlimited analysis with no file size restrictions, plus identification of spamtrap and disposable email domains, you can create a Campaign Cleaner account and subscribe to any plan.

Are You Ready To Experience The Difference?

CC Logo

Become a part of the Campaign Cleaner community today, and join countless satisfied customers who have witnessed significant improvements in their email deliverability and campaign success. Don't let HTML issues hold you back; let Campaign Cleaner optimize your campaigns and boost your inbox rates.

Let's Get Started