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4 articles

12 October 2026 · 12 min read

How to Safely Flatten SPF Record to Avoid Exceeding DNS Lookup Limits

Avoid mail delivery failures by flattening your SPF record, preventing DNS lookup limits and ensuring email deliverability

22 June 2026 · 11 min read

SPF ~all vs -all vs ?all

Soft fail, hard fail, neutral and pass-all: what each SPF qualifier on the all mechanism actually instructs receivers to do, how DMARC changes the picture, and which one to publish at each stage of your rollout.

22 June 2026 · 11 min read

SPF flattening: what it is and when you need it

SPF flattening replaces lookup-based mechanisms with raw IP ranges to dodge the ten-lookup limit. It works, but a hand-flattened record silently goes stale. Here is what flattening really does, the trade-offs, why doing it by hand is risky, and how hosted flattening stays current automatically.

22 June 2026 · 11 min read

SPF records for common email providers

The correct, current SPF includes for Google Workspace, Microsoft 365, Mailchimp, SendGrid, Amazon SES and more, plus how to combine several providers in one record without breaking the 10-lookup limit.