Stop worrying about SPF breaking

SPF flattening replaces the include mechanisms in your SPF record with the resolved IP addresses, reducing the number of DNS lookups. RFC 7208 limits SPF evaluation to 10 DNS lookups — exceed that and receivers return a PermError, which can cause your email to be rejected. Flattening solves this by collapsing your entire SPF chain into direct IP references. mxio’s Managed SPF handles this automatically and keeps your record current as providers change their infrastructure.

RFC 7208 limits SPF record evaluation to 10 DNS lookups. Each include, a, mx, redirect, and exists mechanism counts as one lookup. Organizations using multiple email services (Google Workspace, Microsoft 365, Mailchimp, Salesforce, HubSpot) regularly exceed this limit. When a receiver hits lookup 11, it stops evaluating and returns a PermError — your SPF effectively breaks and emails may be rejected or marked as spam.

Managed SPF starts at $34/month (Basic plan at $19 plus $15/domain add-on) for a single domain. For 3 or more domains, the Pro plan at $59/month is more cost-effective — SPF flattening is included for all 10 domains with no add-on fees. Compare that to AutoSPF at $37 per domain per month. Annual billing saves an additional 17%.

You point your domain’s SPF record at mxio with a single DNS include. From there, everything is managed in your dashboard: toggle email services on and off, add custom IP ranges, and set your SPF policy. mxio resolves all your includes, flattens them to IP addresses, and publishes an optimized record. Background polling detects when providers change their infrastructure and updates your record automatically.

No. Managed SPF validates every record before publishing it to DNS. Your existing authorized senders continue working throughout the process. The dashboard shows a live preview of changes before they go live, and full change history means you can roll back if needed. Health monitoring runs continuously so you know the moment anything changes.

This is the core problem Managed SPF solves. Background polling checks your upstream providers on a regular schedule (every 30 minutes on Pro, every 5 minutes on Business). When a provider like Google or Microsoft updates their SPF includes, mxio detects the change and updates your flattened record automatically. Without this, manually flattened records go stale and legitimate email starts failing.

No. spfflatten.net and mxio.io share one account. You sign up and manage billing on mxio.io, which is the email authentication management platform behind SPF Flatten. Your account includes access to all free tools, domain health monitoring, and any paid features on both sites.

Yes. There are no long-term contracts. Cancel anytime and your plan continues until the end of the current billing period. Your SPF record remains published — you just need to update your DNS to remove the mxio include before the flattened records stop being updated.