Email authentication is a vital procedure for maintaining high email deliverability. Having the slightest chance of your email authentication derailing can and will affect your reputation.
One of the most important email authentication methods there is, the Sender Policy Framework (SPF), an authentication method confirming every email sent using your domain has full authorization by mail servers.
However, SPF records have a limitation: they can only perform 10 DNS lookups before exceeding the permitted limit, leading to potential failures in email authentication.
This is where SPF flattening comes in. SPF flattening tools optimize SPF records by reducing the number of DNS lookups, ensuring better performance and compliance with SPF policies. This blog will explore how SPF flattening works, various tools available—including free SPF flattening tools—and best practices for implementation.
What is SPF Flattening?
Understanding SPF and DNS Lookup Limits
SPF records work by specifying a list of authorized mail servers that can send emails on behalf of your domain. These records contain mechanisms such as include, a, mx, ptr, ip4, and ip6, which require DNS lookups to retrieve the necessary data. The issue arises because SPF lookups are limited to 10 DNS queries, and exceeding this limit causes SPF validation to fail.
How SPF Flattening Works
SPF flattening is a technique that reduces the number of DNS lookups in your SPF record by replacing multiple “include” mechanisms with direct IP addresses. Instead of querying multiple external domains for authorization, SPF flattening consolidates the necessary IPs into a single, optimized SPF record. This ensures compliance with SPF lookup limits and improves email authentication.
Example:
Before SPF Flattening:
v=spf1 include:_spf.google.com include:_spf.mailgun.org include:_spf.salesforce.com -all
Each include statement triggers a separate DNS lookup, contributing to the limit.
After SPF Flattening:
v=spf1 ip4:192.0.2.1 ip4:192.0.2.2 ip4:198.51.100.3 -all
This version eliminates unnecessary DNS queries, improving efficiency.
Why Use an SPF Flattening Tool?
It is possible to perform SPF flattening manually, but it can be extremely tedious, and can increase the risks of errors. This is crucial especially if you are operating a business that employs multiple third-part email services.
SPF flattening tools can automate this process by retrieving all necessary IP addresses and generate a compressed SPF record maintaining compliance with SPF policies.
Benefits of Using an SPF Flattening Tool:
- Prevents SPF authentication failures due to excessive DNS lookups.
- Improves email deliverability by ensuring that all authorized IPs are correctly listed.
- Reduces email rejection rates by minimizing the risk of SPF record misconfigurations.
- Automates record updates, making it easier to manage SPF records when third-party services change their IPs.
- Enhances security by reducing the risk of unauthorized email spoofing.
Best SPF Flattening Tools
PowerDMARC SPF Flattening
Features: Automated SPF record flattening, compliance monitoring, and real-time updates.
Best for: Businesses needing continuous monitoring and compliance.
Website: PowerDMARC
OpenSense SPF Flattening
Features: DNS optimization, real-time SPF record generation, and improved authentication.
Best for: Organizations using multiple email vendors.
Website: OpenSense
Kitterman SPF Record Tester (Free SPF Flattening Tool)
Features: SPF lookup testing, flattening suggestions, and compliance analysis. Best for: Small businesses looking for a free tool.
Website: Kitterman SPF Checker
Mimecast SPF Flattening
Features: Automated SPF flattening and security enhancements. Best for: Enterprises using Mimecast for email security.
Website: Mimecast
How to Use an SPF Flattening Tool: Step-by-Step Guide
Step 1: Perform an SPF Record Lookup
- Before flattening your SPF record, check your current setup using an SPF lookup tool
- Enter your domain name.
- Review the results to see if you are close to or exceeding the 10 DNS lookup limit.
Step 2: Select an SPF Flattening Tool
Choose a tool based on your needs. Free options like Kitterman work well for small businesses, while PowerDMARC and Mimecast SPF flattening are better for enterprises.
Step 3: Generate a Flattened SPF Record
Most SPF flattening tools will automatically:
- Extract all IP addresses from include mechanisms.
- Replace domain references with direct IPs.
- Generate an optimized SPF record.
Step 4: Update Your DNS Settings
- Log in to your domain registrar or DNS provider (GoDaddy, Cloudflare, etc.).
- Locate the SPF record (TXT record) section.
- Replace the old SPF record with the flattened version.
- Save changes and allow time for DNS propagation.
Step 5: Test Your New SPF Record
- Use SPF validation tools like MXToolBox or Kitterman to confirm the updated record is functioning correctly.
- Send test emails and check email headers to ensure SPF authentication is passing.
Best Practices for Using SPF Flattening Services
- Monitor Changes: Regularly review your SPF record to ensure all necessary IPs are included.
- Keep SPF Records Within Limits: Avoid adding excessive include statements to maintain compliance.
- Use DMARC with SPF: Pair SPF with DMARC policies for enhanced email security.
- Automate Updates: Consider using a service like Mimecast SPF flattening to automate updates and minimize manual work.
- Test Before Deployment: Always validate SPF records before final implementation.
Using Warmy to Optimize Your Email Deliverability
Email providers use SPF information to validate incoming email, and having a valid SPF record helps establish trust with these providers.
However, having an SPF flattening is not sufficient. You need to conduct email deliverability audits and utilize various resources to ensure that you have a reputable email domain.
Warmy is an automated all-in-one tool to improve email deliverability that can make your email channel reputable and reliable. Besides its free SPF and DMARC Record generator, it also provides tons of benefits that can help you gain the ability to improve your email deliverability.
Warmy.io SPF and DMARC Record Generator
SPF information is important for email providers to validate incoming emails. SPF flattening tools can help with this
Email providers use SPF information to validate incoming email, and having a valid SPF record helps establish trust with these providers.
However, having an SPF flattening is not enough.
Warmy is well-known for its free email deliverability test that can help you understand any problems you can encounter that might damage your deliverability.
Warmy also offers a free SPF and DMARC Record Generators that helps with the configuration of SPF records which is instrumental for the improvement of email security. It prevents phishing and legacy by allowing domain owners to set email authentication policies and instructs recipients how to handle messages that fail authentication.
DNS Records Testing
Warmy.io has a DNS records testing which can help you test up to 100 DNS records maintaining an optimal email deliverability. This is important for confirming if your emails are being received by your recipient and landing on their inboxes, or are they being sent to spam.
Email Warmups
Sending a high volume of messages can raise some questions for many ISPs and email servers, it harms the trustworthiness of your email domain.
Warmy’s email warmups contributes to the improvement of your email’s reputation by gradually and automatically increasing the volumes of emails you can send, for up to 5,000 emails per day.
Domain Health Hub
Warmy’s Domain Health Hub has been upgraded to a more advanced and professional level, it can now assess every statistical data at a domain level. Users will gain complete monitoring of their deliverability at the domain level instead of their individual inboxes.
- Instant Domain Health Score: Check your deliverability status with metrics such as Inbox Placement, DNS Authentication, and Google Postmaster Data.
- Clear Warm-Up Performance Insights: Gives you the ability to track spam rates, inbox placement, and deliverability trends weekly and monthly.
- Comprehensive DNS Status Checks: Validate and troubleshoot SPF, DKIM, DMARC, rDNS, MX, and A records for seamless email authentication and security.
- Optimized Multi-Domain Monitoring: Manage all your domains from one sleek dashboard. Making it easier to identify which ones need immediate action.
- One-Click Deep Insights: Click on any domain to access detailed health metrics, performance reports, including deliverability trends with ease.
Email Seed List
Seed listing is one of Warmy’s advanced deliverability systems.
It has the flexibility to be integrated into any email client, and improve your email performance testing. Warmy will supply genuine email addresses from Gmail, Outlook — and very soon, Yahoo— that will act as seeds for testing your email deliverability.
It will simulate real engagement to improve sender trust, and if in case that your emails are sent to spam, it will be removed from spam and marked as important to program ISP into understanding that your emails are legitimate.
Customer Success Support, and Deliverability Consultant
We offer 24/7 customer support, via Zoom calls, and chat support, not only for navigating our website, system and tools, but also guarantee that you achieve your long-term goals and acquire reputable emails through our email deliverability programs.
Don’t just acquire an SPF Flattening tool! Start your free 7-day trial, or book a demo.
