Flatten complex SPF records into a clean IP-based SPF with one click. Stay within the 10 DNS lookup limit and ensure your emails always reach the inbox.
Before Flattening:
v=spf1 include:u538675.wl176.sendgrid.net include:_spf.google.com include:spf.protection.outlook.com include:zoho.com include:amazonses.com include:spf.sendinblue.com ~all
After Flattening:
v=spf1 include:kfho42w5d9.powerspf.com ~all
Every domain that sends email should use an SPF record (Sender Policy Framework) to define which servers are allowed to send on its behalf. Many businesses use several email vendors, CRM, marketing tools, transactional email, and forwarding services – each requiring its own SPF mechanism.
Each include, a, mx, or redirect in an SPF record triggers a DNS lookup. The SPF specification caps valid lookups at 10, and exceeding that causes SPF to break (PermError), often resulting in bounced emails, failed authentication, or spam delivery.
As your email infrastructure grows, it’s easy to hit that limit, especially if some includes themselves contain multiple nested lookups. That’s where flattening enters the picture.
SPF flattening is the process of converting an SPF record that contains multiple mechanisms, such as include:, a, mx, or redirect=, into a simplified version that lists the resolved IP addresses directly. Instead of relying on each mechanism to perform DNS lookups during authentication, flattening pre-expands all mechanisms in advance, collects every authorized sending IP from them, and then rewrites the SPF policy using a set of optimized include:
You use multiple email
vendors
CRMs, marketing tools, transactional email services, each adds include lines, pushing your lookup count toward the limit.
Manual SPF record maintenance is error-prone
The process is time-consuming and unsustainable. With every new service, you risk misconfiguration or overshooting limits.
Vendors add/change IP ranges
If vendor-side IP ranges change and you’re using a static, manually flattened record, SPF can break, causing deliverability issues or domain-reputation damage.
Flattening manually might work once, but it’s risky long-term. Email service providers regularly update their sending IP ranges, and if your SPF record remains static, you’ll risk silent failures or deliverability issues.
That’s why our automated SPF Flattening tool is designed to:
| Manual Flattening Issues | Our Tool Solves It |
|
Exceeds 10 DNS lookup limit |
Helps stay under the limit |
|
Prone to human error |
Automatic flattening ensures error-free output |
|
Requires frequent updates |
Auto-updates reduce manual effort |
|
Prone to SPF permerror |
Helps resolve SPF errors |
Automated re-flattening when vendor IPs
change
Zero manual DNS editing or technical expertise
needed
Integrated with DMARC monitoring + threat intelligence
Enterprise-grade SPF optimization ideal for complex setups
Add your domain to instantly auto-detect your active SPF record.
Check your lookup count. Over 10? That’s a red flag!
Our tool instantly flattens the record by resolving domains to their IPs.
The output is a clean, compressed, optimized SPF record with minimized lookups!
For organizations that want the benefits of flattening without its risks, PowerDMARC’s Hosted SPF Macros solution can automatically manage provider IPs without exceeding lookup limits, keeping SPF lighter, more accurate, and maintenance-free.
“PowerDMARC eliminates the SPF lookup limit on our domains with the hosted SPF; we only need to publish 1 SPF record to our DNS.”
Jennifer Heisel
Systems Administrator
“PowerDMARC helps a lot with SPF errors, in particular, by making it easy to do “SPF Folding,” which is often needed for customers who need more SPF includes than are otherwise technically allowed.”
David Spigelman
President
“With SPF flattening, we were able to easily expand the SPF includes to inspect the specifics of the record.”
Dylan Bouterse
Technology Security Consultant
Mailbox providers have a hard time checking your SPF after the 10th lookup, so if your SPF record exceeds the limit, it usually ends with a PermError, and your legitimate emails may start getting rejected or sent to spam.
Flattening doesn’t make SPF more secure; it just helps you stay within the 10-lookup limit, enhancing the accuracy of your SPF setup. Real protection still comes from SPF + DKIM + DMARC working together.
Major email providers like Google and Microsoft update their IPs often, so a manually flattened record can go stale quickly unless you keep refreshing it. A dynamic solution like PowerDMARC resolves this issue.
With manual flattening, any time you add or remove a mail service, or when your provider updates their IP ranges, is a good time to re-flatten your record. If you see sudden SPF failures in reports, that’s another sign it’s time. With our SPF flattening tool, this is automatic and hassle-free.
Traditional Flattening is still useful in certain cases, but not the long-term answer. With vendors changing IPs more frequently and automation becoming the norm, dynamic SPF solutions like PowerSPF are quickly becoming the more reliable approach.
