Email domain
runbox.com email servers, SPF and DMARC
Mail for @runbox.com goes to mx.runbox.com (MX priority 10), as DNS showed on 5 November 2026. The host sits under runbox.com. The domain publishes an SPF record ending in -all and a DMARC policy of p=quarantine, which decide whether mail claiming to be from @runbox.com is trusted.
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runbox.com mail DNS on 5 November 2026
| Priority | MX host | Platform |
|---|---|---|
| 10 | mx.runbox.com | Not identified |
| SPF | v=spf1 include:spf.runbox.com -all |
|---|---|
| DMARC | v=DMARC1; p=quarantine; pct=100; rua=mailto:[email protected] |
| MTA-STS | v=STSv1; id=20190605; |
| TLS reporting | v=TLSRPTv1; rua=mailto:[email protected] |
Read on 5 November 2026 with dig against 1.1.1.1 (8.8.8.8 as fallback); nothing sent to the mail servers. Check the records today with the email provider lookup.
runbox.com MX records
runbox.com publishes a single MX host, mx.runbox.com. With no backup host, a sender that can't reach it queues the message and retries until the server answers or the queue gives up.
runbox.com SPF record
The record on 5 November 2026 was v=spf1 include:spf.runbox.com -all.
In plain terms, it delegates to spf.runbox.com. The top level uses 1 DNS-querying term; SPF allows 10 in total including nested includes (RFC 7208 §4.6.4).
It ends in a hard fail (-all): receivers may reject mail from any server the record does not list.
runbox.com DMARC policy
The record is v=DMARC1; p=quarantine; pct=100; rua=mailto:[email protected].
p=quarantine asks receivers to send failing mail to spam.
Aggregate reports go to runbox.com, so the domain's owner sees who sends mail as @runbox.com.
What that means for you: if a contact gives an @runbox.com address and you send to them, nothing changes. But never put an @runbox.com address in the From line of mail sent through your own tool or ESP. It can't pass DMARC for runbox.com, and this policy tells receivers to junk it.
runbox.com TLS policy
_mta-sts.runbox.com publishes v=STSv1; id=20190605;, so runbox.com uses MTA-STS: sending servers that support it must deliver over verified TLS or not at all (RFC 8461).
It also asks for TLS reports with v=TLSRPTv1; rua=mailto:[email protected] (RFC 8460).
Can you verify @runbox.com addresses?
Our checker treats @runbox.com like any domain: syntax, MX, disposable and role checks first, then a made-up address to rule out a catch-all, then your address at RCPT TO, disconnecting without sending. We have not published a test of how mx.runbox.com answers for @runbox.com, so we make no claim here about whether single mailboxes can be confirmed; each result carries its own reason.
Cleaning a list with these addresses
DNS tells you where mail goes, not whether one person's mailbox still exists. For a list, run the whole file through a verifier before you send: invalid rows come out, risky rows (catch-all, unknown, refused) go in their own segment, and valid rows are safe to mail.
Common questions
- What are the MX records for runbox.com?
- On 5 November 2026:
mx.runbox.com(priority 10). - Does runbox.com have SPF and DMARC?
- On 5 November 2026
runbox.compublished an SPF record ending in-alland a DMARC policy ofp=quarantine. - Is runbox.com a disposable email domain?
- No.
runbox.comis not on the disposable domain list our checker uses, so @runbox.com addresses are checked like any other mailbox. See the disposable domain checker for the list.
Free checks for @runbox.com lists
- Bulk email checker for a pasted list or CSV
- Verify a whole file with a reason for every row
- SPF lookup counter
- MTA-STS checker
- Disposable email checker
Another domain? See every email domain we have mapped and what our checker does at each mailbox provider.
Got a list with @runbox.com addresses?
Sign in with Google and the first 100 addresses are checked free: valid, risky and invalid, with the reason for each row and a file to download. No card. After that, plans start at $9/mo for 2,500 emails a month.
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