In this post, I will show you how an SPF Record can instantly improve your email deliverability.

The Sender Policy Framework (SPF) is an essential email authentication system aimed at preventing email spoofing and enhancing the chances of email delivery. Essentially, an SPF record is a specific type of TXT record within the Domain Name System (DNS) that specifies which mail servers are permitted to send emails on behalf of a particular domain.

When an email server processes an incoming email, the receiving Mail Transfer Agent (MTA) looks up the SPF record associated with the domain found in the envelope from the header. By comparing the connecting server’s IP address to the list of authorized senders in the SPF record, the MTA can assess whether the email is genuine or potentially a spoof, thereby significantly lowering the likelihood of fraudulent emails landing in users’ inboxes. 

The effectiveness of email authentication relies on SPF working together with DKIM (DomainKeys Identified Mail) and DMARC (Domain-based Message Authentication, Reporting, and Conformance). Leading business email services, including Google Workspace, Microsoft 365, Zoho Mail, and Amazon SES, highly recommend proper SPF setup to bolster the credibility of outgoing emails.

Additionally, spam filtering solutions like Mimecast, Barracuda Networks, and Proofpoint utilize SPF as a key indicator in their anti-spam and anti-phishing measures.

How SPF Helps Improve Email Deliverability Instantly

SPF provides organizations and brands with quick advantages by establishing a clear sender policy for their domains. Once the SPF record is published, it offers several key benefits for email deliverability:

• Prevents Unauthorized Senders: Only designated IP addresses and email servers are allowed to send emails “on behalf of” your domain. This robust validation process protects against email spoofing by malicious entities.
  
• Lowers Spam and Phishing Threats: Major email service providers like Gmail, Outlook, and Yahoo Mail, as well as security services such as Cisco Talos, Spamhaus, and SpamExperts, place significant emphasis on SPF verification within their spam-filtering systems. A valid SPF record enhances the chances of your emails reaching recipients’ inboxes rather than being marked as spam.
  
• Supports DMARC Compliance: For compliance with DMARC policies, SPF authentication connects the envelope from domain to your SPF policy. When both SPF and DKIM successfully align, your emails are considered highly trustworthy.
  
• Immediate Results: The benefits of a correctly set up SPF record are almost instantaneous; most receiving mail servers and Mail Transfer Agents will check the SPF policy for every incoming message. Thus, SPF boosts email deliverability as soon as DNS propagation is finished.
  

Common SPF Record Syntax, Mechanisms, and Examples

Understanding SPF Syntax

SPF records follow a specific syntax as outlined in RFC 7208. Each record begins with the version of SPF and includes various mechanisms and qualifiers that collectively specify which IP addresses and hosts are permitted.

Key SPF Mechanisms

• ip4 & ip6: Define permitted IPv4 or IPv6 addresses and ranges. 
  

  Example: `ip4:192.0.2.0/24`

• a & mx: Allow any IP addresses returned from A/AAAA or MX records associated with the domain. 
  

  Example: `mx`

• include: Permits the SPF policy of another domain, which is particularly handy for known senders like SendGrid, Amazon SES, or Mailgun. 
  

  Example: `include:sendgrid.net`

• ptr: (Seldom recommended) Allows mail from IPs that have reverse DNS PTR records matching your domain.
  
• all: Matches every IP address, usually placed at the end of the record with its respective qualifier.
  

SPF Qualifiers

• + (Pass): Explicitly permits (implied when absent).
  
• – (Fail): Clearly denies.
  
• ~ (Softfail): Identifies but does not reject.
  
• ? (Neutral): Indicates no specific policy or preference.
  

SPF Record Examples

Basic SPF Record Example

• v=spf1 ip4:198.51.100.23 include:mailgun.org -all
  

• Only the designated IP address and Mailgun’s servers are authorized to send emails for this domain.
  

Complex SPF Record Example

• v=spf1 ip4:35.190.247.0/24 ip4:64.233.160.0/19 mx include:spf.protection.outlook.com include:_spf.google.com -all
  

• This configuration permits email from specific IP addresses, as well as from Google Workspace and Microsoft 365 (Outlook) servers.
  

How SPF Mechanisms and Qualifiers Work Together

When a server’s IP address aligns with an authorized sender listed in the SPF record, the outcome is an SPF pass. If it doesn’t match, the result — whether it’s an SPF fail, softfail, or neutral — will depend on the specific mechanism and qualifier used. By configuring this accurately, genuine email servers and SMTP relays are more likely to achieve a pass, which enhances email deliverability.

How to Create, Publish, and Test an SPF Record

Planning and Creating an SPF Policy

Prior to launching, conduct a comprehensive inventory of all email sources associated with your domain, including Google Workspace, Microsoft 365, Amazon SES, Mailchimp, newsletters (such as Postmark, Sendinblue, SparkPost), and any bespoke email servers or on-site SMTP relays. It’s essential that each service provides SPF includes or IP addresses to be used as mechanisms.

To minimize syntax mistakes and guarantee policy correctness, many administrators turn to SPF record generators provided by platforms like AutoSPF, Netcore, Trustifi, Fastmail, Namecheap, or Dmarcian.

Publishing SPF in the Domain Name System

1. Access your DNS hosting provider, which could be GoDaddy, Cloudflare, Bluehost, or Namecheap.

2. Create or modify a TXT record at either the domain root or a subdomain:

Set the host/name to `@` or the relevant subdomain.

Input your SPF record string into the value/data field.

3. Save the changes and wait for DNS propagation (usually takes less than an hour). By publishing this as a TXT record in the Domain Name System, you enable MX records and Mail Transfer Agents globally to access and implement your SPF policy.

Testing and Validating Your SPF Record

SPF Validation Tools

Once you’ve made your SPF records public, it’s advisable to utilize an SPF testing tool for verification. Some suggested tools are MxToolbox, EasyDMARC, Dmarcian, and Cisco Talos.

• MXToolbox: Detects syntax mistakes in SPF, evaluates mechanisms, counts lookups, examines policies, and more.
  
• EasyDMARC: Confirms the alignment of DMARC, DKIM, and SPF.
  

Conducting routine checks on your SPF records guarantees that your approved senders consistently pass validation, helping to maintain the best possible email deliverability.

SPF Record Update and Migration

Whenever you incorporate new authorized sending services — such as transitioning to Zoho Mail or integrating with Mailchimp or Barracuda Networks — ensure that you promptly revise your SPF record. During the process of migrating email services (for example, switching to Google Workspace or Outlook), it’s essential to check your SPF alongside related DKIM and DMARC configurations, ensuring that domain alignment remains intact for optimal deliverability.

SPF Best Practices and Mistakes to Avoid

Follow Key SPF Policy Best Practices

• Reduce Includes and Lookups: Be mindful that the SPF lookup threshold is capped at 10 DNS queries per policy. Adding too many includes, particularly for services like SendGrid or Atmail, may lead to SPF failures due to exceeding this limit. Consider using SPF flattening when required.
  
• Authorize Only Essential Senders: Avoid unnecessarily broadening your sender policy by whitelisting unneeded IP ranges or entire networks of providers.
  
• Maintain Clear Syntax: Steer clear of frequent SPF syntax mistakes. Utilize SPF record validators to identify missing or incorrectly placed qualifiers and broken includes.
  
• Monitor Record Size: Records that are too lengthy can surpass DNS limits; streamline or flatten them as needed.
  
• Test Across All Mailflows: Ensure that every outgoing mail scenario — be it transactional, newsletters, or system alerts — is validated with SPF testing tools to confirm successful SPF passing and alignment.
  

Avoid Common Mistakes

• Inadequate Include Chains: Failing to monitor includes may lead to unnecessary lookups or create circular dependencies. It’s essential to assess how these additions affect the SPF lookup limit.
  
• Neglecting Important Providers: Omitting the IP address of a genuine mail server (or the correct MX record) can lead to valid emails encountering SPF failures or softfails, negatively impacting deliverability.
  
• Relying Solely on ‘Neutral’ or ‘Softfail’: An overly lenient SPF policy lacks effectiveness. For most domains, it’s advisable to use `-all` (fail) as the conclusive qualifier unless there is a strong operational justification to do otherwise.
  

Stay Up to Date

Establish a regular timeline for updating your SPF records, particularly after introducing new services, modifying DNS hosting, or during extensive SPF transitions. Ensure that your DKIM and DMARC settings are consistently aligned for optimal email authentication and domain security.

By effectively managing your SPF records, you enhance your domain’s defenses against spoofing, safeguard legitimate sending sources, and achieve maximum email deliverability both now and moving forward.

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In this post, I will give you the DMARC Generator Guide and show you how to create, check, and publish DMARC records.

Email security is no longer optional in today’s threat landscape, making DMARC an essential component of domain protection. This guide explains how to create, check, validate, and publish DMARC records using a DMARC generator.

Whether you’re new to email authentication or looking to strengthen existing protections, you’ll learn how DMARC policies, reporting options, alignment settings, and enforcement levels work together to prevent phishing, spoofing, and unauthorized email use while improving deliverability and domain reputation.

What a DMARC Generator Is and Why It Matters

A DMARC generator tool is an essential solution designed to help organizations quickly and accurately create DMARC records for their domains. As email threats escalate, particularly phishing, Business Email Compromise (BEC), and domain spoofing, implementing a robust DMARC record is crucial for any business prioritizing email authentication and email security. By using a DMARC generator tool, organizations can simplify record creation, reduce configuration errors, and strengthen protection against email-based attacks.

By leveraging a DMARC record generator, security professionals and domain administrators can generate DMARC records with correct syntax and tailored policies—without requiring extensive technical knowledge. Solutions from providers like EasyDMARC, PowerDMARC, and MXToolbox simplify this process, making strong email authentication far more accessible for organizations ranging from Fortune 100 companies to mid-market enterprises.

The DMARC generator walks users through all the necessary tags and options needed to create an error-free DMARC record in the appropriate TXT record format for your DNS zone. This ensures not only basic compliance, but also safeguards your domain against impersonation attacks, ransom threats, and unwanted messages, which can severely damage business reputation and deliverability.

Key DMARC Record Tags Explained: Policy, Alignment, Reports, and Enforcement

DMARC records consist of several policy tags, each representing specific instructions and protocols for mail handling and reporting. Understanding each of these tags is vital when you generate a DMARC record—whether with a generator or manually.

Policy Type (p=): none, quarantine, reject

The policy type is fundamental in any DMARC policy. It tells ISPs and mail receivers what to do with emails that fail DMARC authentication checks:

• none: Monitoring mode. Email messages failing DMARC are still delivered, but you receive reports to your aggregate address. Ideal for initial implementation and analysis.
  
• quarantine: Suspicious emails are routed to the recipient’s spam or junk folder.
  
• reject: The strongest setting, instructing receivers to block delivery of messages failing DMARC validation.
  

Subdomain Policy (sp=)

The subdomain policy specifies what happens to emails sent from subdomains of your primary domain:

• If omitted, the parent domain’s policy applies.
  
• Set as none, quarantine, or reject for tailored subdomain handling.
  

Alignment: SPF and DKIM (aspf=, adkim=)

Alignment tags dictate how strictly the system matches the authorized SPF domain and DKIM signature to the Header From domain (Parent Header From domain):

• SPF alignment (aspf=) and DKIM alignment (adkim=) can be set as relaxed or strict.
  
• relaxed: Allows minor domain mismatches (e.g., sub.example.com and example.com).
  
• strict: Requires an exact domain match.
  

Reporting Options: Aggregate and Failure (RUA, RUF)

Reporting allows you to monitor protocol outcome and fine-tune your DMARC settings:

• Aggregate report (RUA address / rua=): Receives DMARC XML summary reports from ISPs for statistical insights.
  
• Failure report (RUF address / ruf=): Receives forensic or instant DMARC failure reports (forensic report).
  
• Reporting interval (ri=): Determines how often aggregate reports are sent, generally in seconds (e.g., 86400 for daily).
  

Other Tags and Parameters

• Policy percentage (pct=): Applies the policy type to a specified percentage of your mail stream for gradual implementation.
  
• Record type: Always set as a TXT record in your DNS.
  
• Policy tags: Each tag (e.g., p, sp, adkim, aspf, rua, ruf, pct) contributes to clear, enforceable instructions.
  

DMARC Record Format

A valid DMARC record example looks like this:

v=DMARC1; p=quarantine; rua=mailto:dmarc-reports@yourdomain.com; ruf=mailto:forensics@yourdomain.com; adkim=strict; aspf=relaxed; sp=none; pct=100; ri=86400

READ ALSO: Online DMARC Record Generator For Fast Email Security Setup

How to Create a DMARC Record with a DMARC Generator

Deploying a DMARC record begins with properly crafting the record itself. Using a DMARC generator or DMARC record generator streamlines this process, guiding you through each mandatory and optional field.

Steps to Generate DMARC Record

1. Select Your Policy (none, quarantine, reject)

Start by identifying your intended DMARC policy type. New users often begin with none for monitoring, moving gradually to quarantine or reject as authentication improves.

2. Configure Alignment Options

Choose between relaxed and strict modes for SPF alignment and DKIM alignment. This directly affects the stringency of your authentication checks.

3. Input Reporting Details

Enter your RUA address and RUF address for receiving aggregate and forensic DMARC reports. These addresses must be valid mailboxes, ideally separate from main business operations for security.

4. Set Subdomain Policy and Policy Percent

Specify the subdomain policy if you want a different enforcement level for your subdomains. Adjust policy percentage as needed for phased rollouts.

5. Review Generated Syntax

A robust DMARC generator will generate DMARC record syntax and present a valid DMARC ready for DNS entry. Providers such as EasyDMARC, MXToolbox, and PowerDMARC offer intuitive interfaces and instant previews of your configuration.

6. Manual DMARC Record Option

Advanced users may wish to create a manual DMARC record, by following correct tag placement and formatting as described in RFC 7489. However, even experts benefit from generators to avoid common syntax errors.

How to Check, Validate, and Troubleshoot Your DMARC Record

After you generate DMARC record content, validation and troubleshooting are critical.

Using DMARC Checker Tools

Upload your DMARC record to a DMARC checker or record checker like EasyDMARC, MXToolbox, or SuperTool. These tools analyze for:

• Syntax and formatting problems
  
• Correct inclusion of essential policy tags (p, rua, etc.)
  
• Valid RUA/RUF reporting options
  
• Compatibility with your DNS zone and provider
  

Validating in Your DNS

Ensure the DMARC record is published as a TXT record on the _dmarc hostname (Host/Name) in your DNS:

• Example: _dmarc.yourdomain.com as the Name/Host.
  
• Confirm correct record format and ensure your DNS provider (such as GoDaddy) propagates updates quickly.
  

Troubleshooting Common Issues

Syntax and Policy Mistakes

• Missing mandatory tags (such as p)
  
• Incorrect delimiter usage (all tags must end with semicolons)
  
• Malformed reporting addresses (RUA/RUF)
  

Authentication Alignment Errors

• Unmatched SPF identifier or DKIM signature
  
• Incorrect subdomain policy references
  

Achieving an Error-free DMARC Record

Iterate on your record format using both DMARC record generators and manual inspections. Seek out tools and certifications, referencing community reviews from G2 Crowd, Expert Insights, SourceForge, and BetterTracker for authoritative guidance.

How to Publish Your DMARC Record and Move Toward Enforcement

Proper publication of your DMARC policy is essential for full protection and improved deliverability.

Publishing in the DNS Zone

• Access your DNS provider’s management portal (e.g., GoDaddy).
  
• Add a new TXT record at the _dmarc subdomain of your chosen domain.
  
• Paste the content generated by your DMARC record generator as the Value/Data field.
  
• Allow for DNS propagation, which can take from a few minutes to 48 hours depending on your provider and DNS infrastructure.
  

Monitoring and Incremental Enforcement

Upon initial publication, set your policy type to none and review aggregate and failure DMARC reports. Analyze those reports using solutions like Delivery Center to track authentication checks, protocol outcomes, and sources of email traffic.

Gradually migrate from monitoring (none) to quarantine and then reject as your legitimate senders pass SPF and DKIM checks. Carefully review feedback on deliverability to ensure no valid mail is blocked during each phase.

Maintaining and Updating Your DMARC Policy

Regularly review your DMARC records as your email services, subdomains, or partners change. Adjust reporting options or subdomain policy to reflect operational updates, and always verify changes with a DMARC checker before applying them in production.

Taking these steps will ensure a valid, error-free DMARC implementation, maximizing email security, phishing protection, and corporate reputation.

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In this post, we will discuss the security testing routine for teams without a security engineer.

Most companies running a real product do not have a security engineer, and are not going to hire one this year. The salary is out of reach, the role is hard to fill, and there is rarely enough dedicated work to justify a full-time hire until the company is considerably larger. As a result, security testing often ends up owned by nobody in particular, which, in practice, means it only happens when a customer asks for it.

That is a worse position than it sounds, because the absence of a specialist does not mean the absence of a routine. A small team can cover most realistic risks with a schedule, a short checklist, and just a few hours each month.

What follows is a practical routine that works at that scale, organized by how often each task should happen.

Start by Finding Out What You Look Like from the Outside

Before building any schedule, establish a baseline. You cannot plan around risks you have not measured, and most teams have never viewed their own product the way an external attacker would.

The simplest version of this takes about five minutes. Point a web application security scanner at your primary domain and review what it reports about:

• TLS configuration
• Security headers
• Cookie flags
• Information exposed through response headers

This is only a surface-level assessment rather than a complete security review, so it will not uncover deep vulnerabilities. However, it usually identifies several issues that take only a few minutes to fix and may have gone unnoticed for months—or even years.

Document everything the scan finds. That list becomes your starting inventory, and the purpose of the routine below is to prevent those issues from quietly returning.

Every Release: The Five-Minute Checklist

The highest-value habit you can build is a short checklist that runs before every release.

The key is to keep it short. A checklist with thirty items gets ignored. A checklist with five gets used.

Did this change touch authentication or permissions?

If the answer is yes, have a second person review it before merging. Authorization issues remain one of the most damaging categories of web application vulnerabilities and are surprisingly easy to introduce during routine refactoring.

Are there new secrets in the code?

Check for:

• API keys
• Access tokens
• Connection strings
• Credentials

Most major source-code platforms now provide free secret-scanning capabilities. Enable them if you haven’t already.

Did any new endpoint become publicly accessible?

Every new endpoint increases your attack surface.

Someone on the team should be able to clearly explain:

• What the endpoint does
• Who is allowed to access it
• Whether authentication is required

Did dependencies change?

Every new dependency introduces additional code into your application.

Take a moment to verify that newly added packages are actively maintained and have no known critical security concerns.

Is sensitive information being logged?

Application logs should never contain:

• Authentication tokens
• Personal information
• Full request bodies
• Passwords
• Session identifiers

Logging sensitive data is one of the easiest ways to turn a minor security incident into a major compliance problem.

Five honest questions before each release can prevent a surprisingly large percentage of common security mistakes.

Every Week: A Short Security Review

Once each week, dedicate approximately thirty minutes to reviewing three areas.

Review Dependency Alerts

Look through your dependency alerts and actively triage them rather than letting the notification count continue to grow.

Many reported vulnerabilities may not affect the way your application uses a package, but the ones that do deserve prompt attention—not a place in the backlog.

Review Authentication Activity

Spend a few minutes looking for unusual authentication behavior, such as:

• Repeated login failures
• Logins from unexpected locations
• Tokens remaining active longer than expected
• Suspicious account activity

You are not building a full security operations center. You’re simply making a habit of occasionally checking the information already available to you.

Review Security-Related Tickets

Look through any security-related issues opened during the week.

Confirm that each issue:

• Has an owner
• Has a planned resolution date
• Has not quietly stalled

A vulnerability with no owner and no timeline is effectively a vulnerability you’ve decided to keep.

Every Month: Test the Running Application

Weekly reviews help identify gradual changes, but they cannot reveal weaknesses that only become visible when someone actively attacks the running application.

That requires testing the application while it is live.

Historically, this is where smaller organizations struggled.

Traditional penetration testing often costs between $15,000 and $50,000 per engagement and may require several weeks to schedule and complete. For smaller companies, this usually limits testing to once per year.

The problem is that products shipping updates every week accumulate dozens of releases between annual assessments. By the time a penetration testing report arrives, parts of the application may already have changed significantly.

A more practical alternative is to perform testing on a regular monthly schedule using an automated penetration testing tool, while reserving comprehensive manual assessments for major architectural changes, compliance audits, or other high-risk milestones.

More importantly, the testing cadence begins to match the actual development cadence.

Test While Logged In

One detail matters more than the choice of tool itself:

Always test authenticated areas of the application.

Unauthenticated testing primarily examines the public-facing portions of your website.

Authenticated testing reveals the issues that matter most, including:

• Broken access control
• Authorization flaws
• User-to-user data exposure
• Privilege escalation

Create two dedicated test accounts, keep their credentials current, and ensure your testing process consistently uses them.

Every Quarter: Step Back

Four times a year, set aside half a day to review the bigger security picture—things that don’t fit into a weekly routine but can significantly affect your overall security posture.

Review Access Permissions

Start by reviewing who has access to your systems.

Look for:

• Former employees or contractors who still have active accounts
• Unused service accounts
• Cloud permissions granted for temporary projects but never removed

Access reviews are rarely exciting, but they consistently uncover issues that could become serious problems during a security audit—or worse, after a breach.

Verify Your Asset Inventory

Compare your documented inventory with reality.

Make sure you know about every:

• Subdomain
• Staging environment
• Development server
• Third-party integration

Forgotten environments—especially staging systems containing production data—remain one of the most common causes of avoidable security incidents.

If nobody checks for them, nobody remembers they exist.

Test Your Backups

Do not simply confirm that backups exist.

Confirm that they actually restore successfully.

A backup that cannot be restored provides no protection when you need it most.

Reevaluate Your Priorities

Security priorities should evolve alongside your product.

If you recently introduced:

• Payment processing
• Customer portals
• Administrative dashboards
• New APIs

Those areas likely deserve more attention than parts of the application that haven’t changed in years.

Quarterly reviews help ensure your security efforts continue to focus on the areas that matter most.

On Compliance

Many teams begin thinking seriously about security only after:

• An enterprise customer requests SOC 2
• A prospect asks about GDPR
• A security questionnaire appears during procurement

There’s nothing wrong with compliance being the trigger.

The mistake is treating the certification itself as the finish line.

Most compliance frameworks can technically be satisfied with:

• An annual penetration test
• A collection of policy documents
• Security procedures are stored in a shared folder

Unfortunately, none of those things prevents the authorization bug that was introduced during last Tuesday’s deployment.

Teams that consistently build secure products treat compliance differently.

Instead of preparing for an audit once a year, they perform security activities continuously and allow certifications to become a natural by-product of an already healthy process.

The result is not only easier audits—it is a genuinely more secure product.

The Honest Summary

None of this requires a dedicated security engineer.

It simply requires treating security testing as a recurring operational activity instead of something that only happens after an incident or when a customer requests it.

If you want one question to ask at your next team meeting, make it this:

“How would we know if the code we shipped today introduced a security vulnerability?”

If the honest answer is:

• “We’ll find out during the annual penetration test.”

or

• “A customer will probably tell us.”

Then you’ve accurately described your current security posture.

Everything in this routine exists to change that answer.

Solutions designed specifically for development teams—such as penetrify.cloud—exist because annual testing no longer matches the pace at which modern software is built.

Start with a free baseline scan.

Add the five-minute checklist to every pull request.

Schedule one automated security assessment every month.

That small investment of time delivers the majority of the security value, and most teams can put the entire routine in place within a single afternoon.

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