Everything you need to test email deliverability

Email Authentication

Verify your SPF, DKIM, and DMARC configuration with clear pass/fail results and explanations of what each check means. Email authentication is the foundation of deliverability — without it, mailbox providers have no way to verify that your emails are legitimate, which often results in spam folder placement or outright rejection.

SpamBarometer checks your actual email headers against your domain's published DNS records to identify misconfigurations. For example, if your SPF record doesn't include the IP address your email was sent from, or your DKIM signature doesn't align with your From domain, we'll flag it with a clear explanation and steps to fix it.

• SPF record validation and alignment
• DKIM signature verification
• DMARC policy checking and reporting
• Header-from and envelope-from alignment analysis

Learn more about SPF records

SpamAssassin Analysis

Get your SpamAssassin score with a detailed breakdown of every rule triggered and its impact on deliverability. SpamAssassin is the most widely used open-source spam filter, and the rules it applies are representative of what many major mailbox providers use to evaluate incoming email.

Rather than showing you a single score, we list every rule that fired, its point contribution, and a plain-language explanation of what triggered it. This level of detail makes it straightforward to prioritise fixes — a rule adding 3.0 points matters far more than one adding 0.1.

• Rule-by-rule breakdown with scores
• Score impact ranking for prioritisation
• Clear, jargon-free explanations
• Specific remediation guidance for each rule

Learn how spam filters work

Content Analysis

Analyse your email content structure, text-to-HTML ratio, links, and identify potential spam triggers. Content quality is a significant factor in deliverability — emails that are image-heavy, contain excessive links, or use known spam phrases are far more likely to be filtered.

Our content analyser examines the MIME structure of your email, checks all URLs against known blocklists, validates image references, and evaluates the balance between HTML and plain text content. You'll see exactly which elements may be causing problems and what to change.

• Text/HTML ratio analysis and recommendations
• Link validation and blocklist checking
• Spam phrase and pattern detection
• MIME structure and encoding recommendations

AI Recommendations

Get intelligent, actionable suggestions powered by GPT-4 to improve your email content and deliverability. While rule-based analysis tells you what's wrong, our AI goes further by suggesting specific rewrites, structural changes, and engagement improvements tailored to your email.

The AI considers your subject line, preview text, body copy, calls to action, and overall structure. Recommendations are prioritised by impact, so you can focus on the changes that will make the biggest difference to your inbox placement rate. Available on Premium and Enterprise plans.

• Subject line improvements and A/B suggestions
• Body content optimisation for engagement
• Call-to-action and layout recommendations
• Personalisation and segmentation tips