Inbox Mix Report
/inbox-mixPaste a prospect list and see where it will land before you send: the split by mailbox provider, the dead domains, and what that mix means for how you send.
The list never leaves your browser. Only domain names are looked up in public DNS.
What an inbox mix shows
- What it is
Every domain on a list has a mail server, and that server says where the mail lands: Google, Microsoft, a security gateway, or nowhere at all.
- Why it matters
Each provider filters differently. Gateways open every link before a person does, and a domain with no mail server bounces every time.
- Without it
Without the mix, you learn who is on the list from your bounce rate — after the damage is done.
What we check
- The MX record of every unique domain in the list, up to 5,000 domains
- Which provider those mail servers belong to: Google Workspace, Microsoft 365, a security gateway such as Proofpoint or Mimecast, a consumer mailbox, or self-hosted
- Domains with no mail server at all (no MX and no A record), which bounce every time
- What the resulting mix means for which mailboxes to send from, how fast to warm up, and whether to use link tracking
Common questions
Does my list get uploaded?
No. The list is parsed in your browser and only the domain names are sent to public DNS resolvers, the same lookup any mail server does before delivering. Names, addresses and any other columns stay on your machine.
Why does the provider matter?
Each provider filters differently. Google leans on domain reputation and spam-rate data, Microsoft 365 leans on tenant-level reputation and its own link scanning, and security gateways open every link before a person sees the message. Knowing the split tells you which mailboxes to send from and what to expect.
Is a dead domain the same as an invalid address?
No. A dead domain has no mail server, so every address on it bounces. Addresses on live domains can still be invalid; that needs mailbox-level verification, which cannot be done from a browser.