SPF flattening

SPF flattening solves one of the most common SPF problems - exceeding the 10 DNS lookup limit.

SPF flattening drawer showing an over-limit record, sender editing, lookup counts, and the hosted record setup

The problem

Every include, a, mx, and redirect mechanism in your SPF record costs one DNS lookup. If you use multiple sending services - Google Workspace, Mailchimp, Salesforce, HubSpot, and so on - you can easily exceed the 10-lookup limit.

What happens when you exceed the limit

When a receiver evaluates your SPF record and hits more than 10 DNS lookups, the result is a permerror. This means SPF fails for all emails from your domain, regardless of whether the sender is authorized. It's not a soft failure - it's a hard stop.

How SPF flattening works

Suped resolves all include, a, and mx mechanisms in your SPF record into their underlying IP addresses (ip4 and ip6 entries). Since literal IP addresses don't require DNS lookups, this dramatically reduces your lookup count.

The flattened record is hosted on Suped's infrastructure and automatically refreshed as sender IPs change. You don't need to manually update anything when Google or Mailchimp rotates their IP ranges.

Setup

Go to Settings > Domains
Click the three-dot menu on your domain row and select Configure SPF flattening
Use the SPF generator to edit the desired record. Suped loads the saved desired record, or the domain's current SPF record when no desired record has been saved
Click Save record. Suped saves the desired record and hosts a chunked, flattened version
Update your DNS to point to the flattened record (the exact value is shown in the dashboard)
Click Save and verify. Suped verifies the record and shows the current lookup count

Reverting

If you need to stop managing the record through Suped, click Undo in the SPF settings and confirm the removal. This does not change your DNS record, which you must update separately.

Automatic updates

Suped periodically re-resolves all the IP addresses behind your includes. If a sending service adds or removes IPs, the flattened record is updated automatically. This means your SPF record stays accurate without any manual intervention.

Suped