Free Tool

SPF Record Checker

Exceeding 10 DNS lookups in your SPF record causes a permerror — and a permerror fails the same as no SPF at all. Look up your record, see every mechanism parsed, and find out if you're already over the limit.

Get your SPF validation report + DNS lookup breakdown

No spam. Unsubscribe any time.

The SPF Problems That Silently Break Deliverability

The 10-lookup limit — the most common SPF mistake

SPF allows a maximum of 10 DNS-querying mechanisms (include, a, mx, ptr). Every ESP you add uses 1–3 lookups. Klaviyo + SendGrid + Google Workspace + Mailchimp + HubSpot = 5–8 lookups before custom IPs. When you hit 11, receiving servers return a permerror, which fails authentication the same as no SPF.

Why ~all and +all are putting you in spam

~all (soft fail) tells servers that unauthorized senders should be treated with suspicion — but not necessarily rejected. Most servers pass soft-fail emails. +all effectively authorizes every IP on the internet to send for your domain. The correct setting is -all: hard fail unauthorized senders.

Multiple SPF records are invalid

You can only have one SPF TXT record per domain. If two TXT records starting with v=spf1 exist, the entire SPF check returns a permerror. This commonly happens when a new IT admin adds a second record instead of editing the existing one.

SPF and subdomain sending

Your SPF record on the root domain does not cover subdomains automatically. If you send from noreply@mail.yourcompany.com, you need a separate SPF record at mail.yourcompany.com — or the DMARC alignment check will fail even if the root SPF passes.

Fix Your Authentication Stack

SPF Record Builder → DMARC Checker → DKIM Checker → Deliverability Check →

Your SPF Changes the Day You Add a New ESP. Are You Watching?

InboxEagle monitors your SPF record daily — detecting changes, lookup count increases, and new mechanisms added by your team or third-party services. You get an immediate alert when the record changes and a weekly digest showing your full authentication health. Trusted by 2,000+ brands.

Start Free 14-Day Trial

No credit card required · Cancel anytime

Not ready yet? See how SPF Monitoring works →