Insights

Weekly, data-grounded reads on how the world configures email, drawn from our live Email Infrastructure Index. Aggregate DNS only, no personal data.

Who actually enforces DMARC? Reject rates by email provider

Thu, 02 Jul 2026 · Enforcement isn't uniform, where a domain is hosted predicts whether it's protected.

The IPv6 email mirage: 55.2% of MX "support" it, but two companies carry the entire story

Sat, 11 Jul 2026 · Google runs IPv6 on 100% of its inboxes, Microsoft on 91.3%. Take those two out and IPv6 email adoption collapses to 12.9%.

The DMARC enforcement gap: 64.6% publish it, only 22.8% enforce it

Thu, 02 Jul 2026 · Most domains that publish DMARC never actually turn it on. Here's the data.

83.4% of the web's email runs on just 3 providers

Thu, 02 Jul 2026 · A handful of gatekeepers receive most of the world's mail. What it means for senders.

The email authentication funnel: 91.5% publish SPF, only 26.1% actually reject

Thu, 02 Jul 2026 · Follow mail-enabled domains from "publishes a record" to "enforces it." Most drop out.

State of email: 80.6% mail-enabled, 76.5% SPF, 64.6% DMARC

Thu, 02 Jul 2026 · A one-glance snapshot of how the internet configures email right now.

50.4% of SPF records use ~all (softfail), most email says "maybe"

Thu, 02 Jul 2026 · Among domains that publish SPF, softfail still beats hardfail. What that costs you.

Who runs the world's inboxes? MX market share across 50,000 domains

Thu, 02 Jul 2026 · Google, Microsoft, self-hosted, and a very long tail. Why deliverability is hard.

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